Light Steel Frame Housing

by HUD USER

U.S. Department of Housing and Urban Development
Office of Policy Development and Research

Residential Steel Framing

Fire and Acoustic Details

September 2002

Residential Steel Framing – Fire and Acoustic Details

PATH (Partnership for Advancing Technology in Housing) is a new private/public effort to develop, demonstrate,
and gain widespread market acceptance for the “Next Generation” of American housing. Through the use of new or
innovative technologies, the goal of PATH is to improve the quality, durability, environmental efficiency, and
affordability of tomorrow’s homes.

PATH is managed and supported by the Department of Housing and Urban Development (HUD). In addition, all
Federal Agencies that engage in housing research and technology development are PATH Partners, including the
Departments of Energy and Commerce, as well as the Environmental Protection Agency (EPA) and the Federal
Emergency Management Agency (FEMA). State and local governments and other participants from the public
sector are also partners in PATH. Product manufacturers, home builders, insurance companies, and lenders represent
private industry in the PATH Partnership.

To learn more about PATH, please contact:

451 7th Street, SW
Washington, DC 20410
202-708-5873 (fax)
e-mail: pathnet@pathnet.org
website: www.pathnet.org

Visit PD&R's Web Site
www.huduser.org
to find this report and others sponsored by
HUD's Office of Policy Development and Research (PD&R).

Other services of HUD USER, PD&R's Research Information Service, include listservs; special interest, bimonthly
publications (best practices, significant studies from other sources); access to public use databases; and hotline
1-800-245-2691 for help accessing the information you need.

Residential Steel Framing
Fire and Acoustic Details

Prepared for

The U.S. Department of Housing and Urban
Development
Office of Policy Development and Research
Washington, DC

and

Steel Framing Alliance (SFA)
Washington, DC

by

NAHB Research Center, Inc.
400 Prince George's Boulevard
Upper Marlboro, MD 20774-8731

Contract No. H-21310CA

September 2002

Residential Steel Framing – Fire and Acoustic Details

Disclaimer

While the information in this document is believed to be accurate, neither the
authors, nor reviewers, nor the U.S. Department of Housing and Urban
Development, nor the Steel Framing Alliance, nor the NAHB Research Center, Inc.,
nor any of their employees or representatives make any warranty, guarantee, or
representation, expressed or implied, with respect to the accuracy, effectiveness, or
usefulness of any information, method, or material in this document, nor assumes
any liability for the use of any information, methods, or materials disclosed herein,
or for damages arising from such use.

Notice: The contents of this report are the views of the contractor and do not
necessarily reflect the views or policies of the U.S. Department of Housing and
Urban Development or the U.S. Government. The U.S. Government does not
endorse producers or manufacturers. Trade and manufacturers’ names appear
herein solely because they are considered essential to the contents of this report.
ii

Residential Steel Framing – Fire and Acoustic Details

Acknowledgements

This report was prepared by Nader Elhajj, P.E., for the U.S. Department of Hosing
and Urban Development (HUD) and the Steel Framing Alliance (SFA). Special
appreciation is extended to Bill Freeborne of HUD and Kevin Bielat of the Steel
Framing Alliance for their guidance and assistance throughout the project. David
Dacquisto provided technical review. Linda Marchman provided administrative
assistance.

Appreciation is especially extended to members of the steering committee, listed
below, whose input contributed to this work.

Kevin Bielat American Iron and Steel Institute
Nader Elhajj NAHB Research Center
Bill Freeborne U.S. Department of HUD
Steve Fox Canadian Sheet Steel Building Institute
Philip Grankowski National Evaluation Service, Inc. (NES)
Jonathan Humble American Iron and Steel Institute
Greg Ralph Dietrich Industries, Inc.
Jay Larson Bethlehem Steel Corp.
Bud Waters Hunt Building Corporation
Dean Peyton Anderson-Peyton Consulting Engineers
Jeffrey Proster Brookfield Homes
Thomas Sheppard Unites States Gypsum
Tim Waite Steel Framing Alliance
Edward Wirtschoreck National Evaluation Service, Inc. (NES)

iii

Residential Steel Framing – Fire and Acoustic Details

iv

Residential Steel Framing – Fire and Acoustic Details

Forward

The NAHB Research Center, U.S. Department of Housing and Urban
Development (HUD) and the Steel Framing Alliance have worked cooperatively
to introduce cold-formed steel framing into the residential construction market
and to provide objective builders and homeowners with a cost-effective
alternative construction material. To accomplish this objective, many barriers
have been overcome. However, one of the remaining barriers is the lack of
adequate fire and acoustic details.

In response, HUD and the Steel Framing Alliance commissioned the NAHB
Research Center to review current knowledge and develop a comprehensive list of
fire and acoustic ratings for tested cold-formed steel assemblies. This “listing” is a
state-of-the-art resource for the residential and light commercial building
designers. A list of needed details and construction assemblies is also identified
and recommended for testing.

Harold L. Bunce
Deputy Assistant Secretary for
Economic Affairs

v

Residential Steel Framing – Fire and Acoustic Details

vi

Residential Steel Framing – Fire and Acoustic Details

Executive Summary

Cold-formed steel has been widely used in commercial buildings, especially in
non-load bearing (partitions) and curtain wall applications. Cold-formed steel
sections are increasingly being used as primary structural members, such as
beams, floor joists, and load-bearing walls in commercial and residential
construction.

Despite the availability of cold-formed steel framing, there are still basic barriers
that impede its adoption in the residential market. Probably one of the primary
barriers is that the building industry is generally reluctant to adopt alternative
building methods and materials unless they exhibit clear quality or performance
advantages. The fire and acoustical performance of cold-formed floor and wall
assemblies are important considerations when designing residential and light
commercial structures. However, there is little information available in the United
States (US) on fire ratings and sound transmission class ratings of cold-formed
steel assemblies and the available information is dispersed and not readily
accessible to end users.

This report investigates regulatory requirements, available test data, and typical
practices relating to acoustics and fire protection of cold-formed steel framing.
The intention is to give an overview of current regulations, as well as a “snap
shot” of available fire and acoustic cold-formed steel assemblies.

This document starts by providing an overview of fire and acoustic requirements
of cold-formed steel assemblies and the characteristics of such assemblies as
related to fire and acoustic performance. A detailed description of current building
codes and building code requirements for the fire protection and acoustical
insulation of cold-formed steel assemblies follows. A comprehensive list of tested
fire- and sound-rated assemblies is provided. Finally, recommendations are given
to direct future tests and research.
vii

Residential Steel Framing – Fire and Acoustic Details

viii

Residential Steel Framing – Fire and Acoustic Details

Contents

LIST OF TABLES --------------------------------------------------------------------------------------- XI
LIST OF FIGURES ------------------------------------------------------------------------------------- XII
GLOSSARY --------------------------------------------------------------------------------------------- XIII
1 INTRODUCTION -------------------------------------------------------------------------------------- 1
1.1 OBJECTIVE----------------------------------------------------------------------------------------- 1
1.2 RESIDENTIAL COLD-FORMED STEEL FRAMING ----------------------------------------------- 1
1.3 INTEGRATION OF FIRE AND ACOUSTIC PERFORMANCE--------------------------------------- 2
2 FIRE CHARACTERISTICS OF COLD-FORMED STEEL FRAMING------------------- 3
2.1 INTRODUCTION------------------------------------------------------------------------------------ 3
2.2 COLD-FORMED STEEL AT ELEVATED TEMPERATURES --------------------------------------- 3
2.3 FIRE PROTECTION OF COLD-FORMED STEEL FRAMING BY GYPSUM BOARD -------------- 4
2.4 IMPORTANCE OF FIRE PROTECTION------------------------------------------------------------- 5
3 ACOUSTIC CHARACTERISTICS OF COLD-FORMED STEEL FRAMING ---------- 6
3.1 INTRODUCTION------------------------------------------------------------------------------------ 6
3.2 FUNDAMENTALS OF SOUND TRANSMISSION --------------------------------------------------- 6
3.3 METHODS OF MEASUREMENT ------------------------------------------------------------------- 9
3.3.1 Single Figure Ratings --------------------------------------------------------------------10
3.4.2 Spectrum Adaptation Terms -------------------------------------------------------------10
3.3.3 Frequency Ranges ------------------------------------------------------------------------10
3.4 ACOUSTIC CHARACTERISTICS OF COLD-FORMED STEEL FRAMING------------------------10
3.4.1 Separating Walls --------------------------------------------------------------------------12
3.4.2 Separating Floors-------------------------------------------------------------------------13
3.4.3 Impact Sound Transmission -------------------------------------------------------------14
4 BUILDING CODES, CLASSIFICATION AND OCCUPANCY ----------------------------16
4.1 INTRODUCTION-----------------------------------------------------------------------------------16
4.2 U.S. BUILDING CODES --------------------------------------------------------------------------16
4.2.1 Model Code Organizations --------------------------------------------------------------16
4.2.2 Methods of Approval ---------------------------------------------------------------------20
4.3 BUILDING CLASSIFICATION---------------------------------------------------------------------21
4.3.1 IBC Use and Occupancy Classification------------------------------------------------21
4.3.2 Types of Construction --------------------------------------------------------------------22
5 FIRE AND ACOUSTIC CODE REQUIREMENTS -------------------------------------------23
5.1 INTRODUCTION-----------------------------------------------------------------------------------23
5.2 FIRE REQUIREMENTS ----------------------------------------------------------------------------23
5.2.1 IBC Fire Requirements-------------------------------------------------------------------25
5.2.2 BOCA Fire-Resistance Requirements --------------------------------------------------28
5.2.3 UBC Fire-Resistance Requirements ---------------------------------------------------29
5.2.3 SBC Fire-Resistance Requirements----------------------------------------------------30
5.2.4 IRC, CABO and ICC IOTFDC Fire Requirements -----------------------------------31
ix

Residential Steel Framing – Fire and Acoustic Details

5.3 ACOUSTICAL REQUIREMENTS ------------------------------------------------------------------33
5.4 DETERMINATION OF FIRE AND ACOUSTIC RATINGS -----------------------------------------34
5.4.1 Determination of Fire-Resistance Ratings---------------------------------------------34
5.4.2 Determination of STC and IIC Ratings-------------------------------------------------35
6 FIRE AND ACOUSTIC DETAILS - INDUSTRY LITERATURE -----------------------37
6.1 INTRODUCTION-----------------------------------------------------------------------------------37
6.2 FIRE-RATED ASSEMBLIES ----------------------------------------------------------------------37
6.3 ACOUSTIC ASSEMBLIES -------------------------------------------------------------------------41
7 FIRE-RATED AND ACOUSTIC PERFORMANCE RATED DETAILS ---------------43
7.1 FIRE RATED ASSEMBLIES-----------------------------------------------------------------------43
7.1.1 Walls----------------------------------------------------------------------------------------43
7.1.2 Floors---------------------------------------------------------------------------------------54
7.2 STC AND IIC RATED ASSEMBLIES ------------------------------------------------------------56
7.2.1 Walls----------------------------------------------------------------------------------------57
7.2.2 Floors---------------------------------------------------------------------------------------59
8 SUMMARY OF RESEARCH ON FIRE RATING AND ACOUSTIC
PERFORMANCE OF COLD-FORMED STEEL FRAMING ----------------------------61
8.1 INTRODUCTION-----------------------------------------------------------------------------------61
8.2 FIRE RATING RESEARCH SUMMARY-----------------------------------------------------------61
8.2 ACOUSTICAL PERFORMANCE RESEARCH SUMMARY ----------------------------------------64
9 FIRE AND ACOUSTIC RESEARCH AND TESTING NEEDS FOR RESIDENTIAL
APPLICATIONS -----------------------------------------------------------------------------------65
9.1 INTRODUCTION-----------------------------------------------------------------------------------65
9.2 RESEARCH NEEDS -------------------------------------------------------------------------------65
10. REFERENCES---------------------------------------------------------------------------------------69

APPENDIX A - LIST OF U.S. FIRE- AND SOUND-RATED STEEL ASSEMBLIES
APPENDIX B - LIST OF CANADIAN FIRE- AND SOUND-RATED STEEL ASSEMBLIES
APPENDIX C – METRIC CONVERSION
x

Residential Steel Framing – Fire and Acoustic Details

List of Tables

Table 3.1 - STC Of Various Construction Materials ---------------------------------------------------- 7
Table 3.2 - Comparative Performance of Sound Insulation For An Ambient Noise Level
of 30db-------------------------------------------------------------------------------------------------- 7
Table 4.1 - International Codes - Adoption By State---------------------------------------------------19
Table 4.2 – Assembly Group Occupancy (Based On 2000 IBC) -------------------------------------22
Table 4.3 - Types Of Construction (2000 IBC) ---------------------------------------------------------22
Table 5.1 - Required Separation Between Dwelling Units (Hours) ----------------------------------25
Table 5.2 – Fire-Resistance Rating Requirements For Building Elements (Hours)----------------26
Table 5.3 – Fire-Resistance Rating Requirements For Exterior Walls Based on Fire Separation
Distance (Hours) -------------------------------------------------------------------------------------26
Table 5.4 – Fire Wall Fire-Resistance Ratings----------------------------------------------------------27 
Table 5.5 – Required Automatic Fire Sprinkler (AFS) Per 2000 IBC and 2000 IRC--------------27
Table 5.6 – Fire-Resistive Requirements For Structural Components Per The 1999 NBC -------28
Table 5.7 – Fire-Resistive Requirements For Structural Components Per The 1997 UBC -------29
Table 5.8 – Fire-Resistive Requirements For Structural Components Per The 1999 SBC--------30
Table 5.9 – Fire-Resistant Separation Requirements in The IRC, CABO & OTFDC -------------31
Table 5.10 - STC And IIC Requirements Selected Codes---------------------------------------------33
Table 5.11 - Test Methods For Fire-Rated Steel Assemblies -----------------------------------------34
Table 5.12 - Test Methods For Acoustical Insulation --------------------------------------------------35
Table 6.1 - Summary of Industry Literature-------------------------------------------------------------38
Table 6.2 - Fire-Resistance Design Manual-Gypsum Systems ---------------------------------------40
Table 6.3 – Fire Ratings of Tested Cold-Formed Steel Assemblies----------------------------------41
Table 6.4 - Summary Of Industry Literature ------------------------------------------------------------42
Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing ---------------------------------------43
Table 7.2 – Fire-Rated Wall Assemblies – Load Bearing ---------------------------------------------50
Table 7.3 – Fire-Rated Floor Assemblies----------------------------------------------------------------54
Table 7.4 – Non-Load Bearing Walls – STC Rating ---------------------------------------------------57
Table 7.5 – Load Bearing Walls – STC Rating ---------------------------------------------------------58
Table 7.6 – STC/IIC Rated Floor Assemblies-----------------------------------------------------------59
xi

Residential Steel Framing – Fire and Acoustic Details

List of Figures

Figure 1.1 Typical Cold-Formed Steel Sections

2
Figure 2.1 Strength of Steel at Elevated Temperatures Relative to Normal
Yield Strength

4
Figure 3.1 Direct and Flanking Transmission

9
Figure 3.2 Schematic Showing the Principle of Double Layer Construction with
Associated Acoustic Benefit

11
Figure 3.3 Sound Transmission Paths Through Cold-Formed Steel Walls

12
Figure 3.4 Typical Characteristics of a Double Steel Stud Separating Wall

13
Figure 3.5 Impact Sound with Different Surface Layers

14
Figure 4.1 Geographical Distribution of the I-Codes

18

xii

Residential Steel Framing – Fire and Acoustic Details

Glossary

Absorbers. Materials that have the capacity to absorb sound, such as acoustical tile and panels,
carpeting, draperies and upholstered furniture.

Acoustics. The science of sound, including its production, transmission, and effect.

Acoustic boards. These boards are denser than regular wallboard but somewhat more flexible. As
a general rule they Acoustic Boards give a sound reduction of about 2 dB greater than regular
wallboard in typical partitions.

Decibel. A unit adopted for convenience in representing vastly different sound pressures. It is 20
times the logarithm to the base 10 of the ratio of the sound pressure to a reference pressure of
0.0002 dyne/cm
2
. This reference pressure is considered the lowest value that the ear can detect.

Draft Stop. Building materials installed in concealed passages of building components such as
attics, crawl spaces, and ceiling/floor assemblies to restrict the movement of air, smoke, and
gases through large passages within those components to other areas of the building.

Frequency. The number of times that an action occurs in a given time period. In sound, the
number of complete vibration cycles per second represented by the unit hertz (Hz).

Fire Separation. A construction assembly that acts as a barrier against the spread of fire.

Fire-Resistance. Fire-resistance designates the ability of a laboratory-constructed assembly to
contain a fire in a carefully controlled test setting for a specified period of time.

Fire-Resistance Rating. The time in hours or fractions thereof that a material or assembly of
materials will withstand the passage of flame and the transmission of heat when exposed to fire
under specified test and performance criteria as prescribed by the applicable code.

Firestopping (or Fireblocking). Building materials installed to prevent or slow the movement of
flames and gases to other areas of a building through small concealed passages in building
components such as floors, walls, and stairs.

Fire Protection System. System, such as water fed sprinklers that provide early and automatic
detection and suppression of developing fires.

Firewall. A type of fire separation of noncombustible construction which subdivides a building
or separates adjoining buildings to resist the spread of fire and which has a fire-resistance rating
as prescribed by the applicable building code and has sufficient structural stability under fire
conditions to allow collapse of construction on either side without collapse of the wall.

Hertz (Hz). The unit of measure of frequency, representing cycles per second. Named for
Heinrich R. Hertz, noted German physicist.

Impact Insulation Class (IIC). A numerical evaluation of a floor-ceiling assembly’s effectiveness
in retarding the transmission of impact sound. The U.S. Federal Housing Administration
developed this single number rating.
xiii

Residential Steel Framing – Fire and Acoustic Details

Impact Noise Rating (INR). A single-number rating based on standardized test performance, for
evaluating the effectiveness of assemblies in isolating impact sound transmission. INR rating
method is being replaced by the Impact Insulation Class (IIC).

Impact Sound Pressure Level (ISPL). The sound pressure (in decibels) measured in a receiving
room, resulting from the transmission of impact sound through a floor construction, produced by
a standard “tapping” machine.

Occupancy. The use or intended use function of a building or part thereof for the shelter or
support of persons, animals, or property.

Occupancy Classification. The level of hazard associated with identification of the occupancy of
the building dictates a level of fire-resistance necessary to protect the occupants of the building.

Octave. The interval between a sound of one frequency and a sound with a frequency that is
exactly double the first.

Octave Band. A frequency spectrum, which is one octave wide. Bands of one-third octave are
used for recording sound test results and are designated by the center frequency of the band.

Party Wall. A fire wall on an interior lot line used or adapted for joint service between two
buildings (such as between townhouses).

Sound Pressure level (SPL). Expressed in decibels, the SPL is 20 times the logarithm to the base
10 of the ratio of the pressure of sound to the reference pressure 0.0002 dynes per square
centimeter.

Sound. The transfer of sound energy from one place to another, through air, structure, or other
conductor.

Sound Transmission Class (STC). A rating system used to measure the insulation (or isolation) of
airborne sound provided by a barrier. STC is determined from a sound-transmission-loss curve
obtained from a standardized test of a large-scale specimen. The higher the STC rating, the more
soundproof the construction.

Sound Transmission Loss (STL). The difference between the sound energy (sound pressure level)
in a source room and a receiving room when the two rooms are separated by the system being
tested. In general, the transmission loss increases with frequency, i.e. the higher the frequency
the greater the sound transmission loss.

Wallboard. The most common gypsum board used. Typically the gypsum core density is 44.9
lb/ft
3
(720 kg/m
3
) giving a wallboard mass of about 1.85 lb/ft
2
(9 kg/m
2
) for 1/2” (12.5 mm)
board thickness. Standard thicknesses are 9.5 mm (3/8”), 7/16” (12 mm), 1/2” (12.5 mm), 9/16”
(15 mm), 5/8” (15.9 mm), and 3/4" (19 mm). Standard width is 48 inches (1200 mm).

xiv

Residential Steel Framing – Fire and Acoustic Details

1 Introduction

There are increasing demands for improvements in standards of construction quality, comfort
and performance in housing. The residential construction market in the United States (U.S.) is
constantly looking for new and improved methods for construction of residential buildings.

The market for cold-formed steel (CFS) framing in residential construction is potentially large as
the construction benefits of durability, high strength, reliability, versatility recyclability, long
life, and adaptability are realized.

An important consideration in many residential construction applications is fire and acoustical
performance. However, this information is not easily found and may not be available for
construction assemblies most relevant to residential construction. Therefore, this report provides
an overview of the current U.S. building codes requirements related to fire and acoustic
performance, and a compilation of fire- and acoustic-rated CFS assemblies. From this initial
effort, additional fire and acoustic assemblies were identified for future tests and ratings.

This report focuses on residential construction, however, certain sections address light
commercial applications, as the two markets possess similar characteristics when fire and sound
ratings are involved.

1.1 Objective

The objectives of this report is:

• To increase the understanding of the acoustic and fire performance of CFS framing
construction.
• To provide information on required levels and fire protection performance for dwellings
using cold-formed steel framing.
• To provide information on fire and acoustic issues to consider when designing buildings with
cold-formed steel framing.
• To identify gaps in available information to direct future research and dissemination activity.

1.2 Residential Cold-Formed Steel Framing

Light steel framing is now used successfully for housing in many countries (such as Canada,
Australia, Japan, Korea, and the U.S.). In the United States approximately 1% of new housing
starts are CFS [1]. CFS is also being used for applications such as fire separation walls within hot
rolled steel-framed apartment and commercial buildings.

CFS framing is a term commonly used to refer to light-gauge steel members with thicknesses
ranging from 0.033 to 0.118 inches (0.84 to 3.00 mm) that are produced by roll forming. These
members may be wall studs, track, floor joists, roof rafters, bridging channels, furring channels,
or related accessories (see Figure 1.1). Also included are non-load bearing drywall studs, which
1

Residential Steel Framing – Fire and Acoustic Details

have a steel thickness ranging from 0.018 to 0.033 inches (0.46 to 0.84 mm). CFS construction
can use individual steel components or prefabricated panels, assembled on site using self-tapping
screws to create a whole building structure.

The Steel Framing Alliance in cooperation with HUD and the NAHB Research Center, have
standardized the residential steel framing members and produced a prescriptive approach to
residential cold-formed steel framing [2]. This prescriptive approach was later adopted by U.S.
building codes including the 1995 CABO One- and Two-Family Dwelling Code [3], the 1998
International One and Two Family Dwelling Code [17] and the International Residential Code
(2000 IRC) [4].
SFS C section
Zed section
Plain C section Lipped C section
Multichannel
Swagebeam
Multibeam
Box C sectionBack-to-back
C sections
Figure 1.1 – Typical Cold-Formed Steel Sections

1.3 Integration of Fire and Acoustic Performance

Any evaluation of a construction method must look not only at the structural requirements but
also at the total performance of the building. Two current technical issues regarding residential
(and commercial) buildings are fire-resistance and acoustic performance. The methods used to
achieve good acoustic performance and protection from fire are often similar and have an impact
on each other. Requirements for fire separation and acoustic insulation in many building codes
affect the same elements of the construction.

Principally, “acoustic separation is required in common interior walls, partition and floor ceiling
assemblies between adjacent dwelling units and between adjacent dwelling units and adjacent
public areas such as halls, corridors, stairs or service areas (Section 1206.1 of 2000 IBC [21]).
Methods for achieving fire protection and good acoustic performance of CFS framing are
2

Residential Steel Framing – Fire and Acoustic Details

inevitably closely linked, and the provision of acoustic and fire separation is often achieved
using the same constructions and materials.

2 Fire Characteristics of Cold-Formed Steel Framing

2.1 Introduction

Cold-formed steel (CFS) is widely used in commercial buildings, especially in non-load bearing
(partitions) and curtain wall applications. CFS sections are also used as primary structural
members such as load-bearing walls in commercial and residential construction. Although in
single family dwellings CFS sections are not required to be fire resistant, in multi-family and
commercial construction these members are often required to be fire resistant when they are part
of a fire separation wall or where they support other floors required to be fire-resistant,
floor/ceiling or roof ceiling assembly which includes structural elements such as columns, beams
and girders.

Building codes frequently require a fire-resistance rating for steel-framed assemblies. The rating
is based on fire tests conducted in accordance with recognized standard test methods. Fire rating
of an assembly is a measurement that indicates how long the assembly will resist the spread of
fire while maintaining structural integrity. Fire-resistance ratings are expressed by the number of
hours (or minutes) that a wall assembly can maintain its integrity while containing the fire,
smoke, and temperature of a working fire.

Life safety, and specifically fire protection, has been and will always be a primary concern of the
building codes. Current U.S. building codes have significant requirements regulating the use of
fire-rated assemblies, the installation of fire stopping (or fire blocking), draft stopping, and fire
suppression systems.

Fire protection and fire separation between dwelling units are becoming more significant issues
for the CFS framing industry as the technology is being adopted for taller apartment buildings
and multi-family dwellings. Similarly, apartment buildings present additional acoustic separation
challenges, particularly in floor construction. Furthermore, CFS frame elements are increasingly
being integrated into steel framed buildings and the acoustic and fire performance data is needed.

2.2 Cold-Formed Steel at Elevated Temperatures

Cold-formed steel-framed structures are inherently non-combustible, and do not contribute to fire
spread. However, the load bearing capacity of steel at elevated temperatures depends on the
temperature level and temperature distribution within the steel components. CFS possesses little
fire-resistance because the steel sections tend to heat up quickly if directly exposed to fire.
Therefore, it is imperative to provide some additional fire protection in most applications to
ensure stability of the structure or the integrity of structural walls in fire conditions.

3

Residential Steel Framing – Fire and Acoustic Details

The modulus of elasticity and strength of steel decrease as its temperature rises and the
temperature gradient through the section causes additional bending moments in the stud.
According to a British Steel report [5], steel is maintained at its full strength until it reaches a
temperature of 750ºF (400ºC). Above that temperature the strength quickly decreases. The loss
of strength (yield strength) of CFS at elevated temperatures exceeds that of hot rolled steel by
between 10 and 20% based on data obtained from tests performed by British Steel [5] as
represented in Figure 2.1. According to tests conducted in the United States [6] using the ASTM
E119 [7] method, average steel temperatures at wall failure ranged from 740ºF (390ºC) to over
1000ºF (530ºC) with one wall attaining temperatures of 1,800ºF (980ºC). This wide range of
failure temperatures illustrates that endurance under fire conditions is more dependent on the
composition of the assembly than on the steel itself. Moreover, Klippstein [6] concluded that the
size of steel sections has an effect on the load bearing capacity as the temperature increases.
Thus, structural integrity during a fire is dependent on fire protection measures.

Fire protection measures can be achieved in a number of ways, but most commonly appropriate
(board) coverings are used to surround the steel with fire resisting materials. Board materials
such as gypsum boards, cementitious boards or gypsum fiberboards for walls and ceilings and
timber based boards for floors can readily provide up to 120 minutes of fire protection. The use
of mineral wool insulation materials also adds to the fire protection.

Strength of Steel at Elevated Temperatures Relative to Normal
Yield Strength
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 100 200 300 400 500 600 700 800
Temperature (ºC)
Strength Retension
Cold-
Formed
Steel
Hot
Rolled
Steel
Figure 2.1 - Strength of Steel at Elevated Temperatures Relative to
Normal Yield Strength
Source: British Steel [5]

2.3 Fire Protection of Cold-Formed Steel Framing By
Gypsum Board

CFS framing generally achieves fire separation by the use of layers of gypsum board. When
exposed to fire the free water and chemically combined water in the gypsum is gradually driven
off at temperatures above approximately 212ºF (100ºC). This causes a temperature plateau on the
4

Residential Steel Framing – Fire and Acoustic Details

unexposed face of the lining. This process of removal of chemically combined water is called
calcination and results in a loss of strength and shrinkage of the sheet material. The resultant
product is a powder, which has much less strength than the original gypsum. Further gradual
product disassociation occurs at temperatures exceeding 392ºF (200ºC).

Gypsum panel and plasterboard manufacturers typically provide fire data based on laboratory
fire tests. In the U.S., these tests are carried out to ASTM E119 [7]. In general, a fire-resistance
rating of 30 minutes is readily achievable using one layer of 1/2-inch (12.8 mm) gypsum
wallboard and 60 minutes is achieved using multiple layers of gypsum wallboard. Greater
periods of fire protection are also possible using additional layers. Cementitious board or gypsum
fiberboard of varying thickness can also be used to replace one or more of the gypsum boards.
Furthermore, when multiple layers of boards are used, their joints should be staggered to
maximize integrity in fire.

2.4 Importance of Fire Protection

Building codes typically set the acceptable height and area limits of buildings based on the
combustion characteristics of the structure. Because low-rise residential buildings are typically
smaller than other types of buildings, they only have to meet minimum fire requirements. Such
construction is often termed “Combustible – Unprotected” in building codes (for single family
dwellings and townhouses).

Fire ratings and fire separation requirements vary based on the type of construction. All U.S.
building codes require that exterior wall construction within some distance from the property line
be of one-hour construction. One-hour fire resistive walls that are continuous to the underside of
the roof sheathing, on the other hand, must separate dwelling units in a two-family dwelling. A
two-hour separation is usually required between townhouse units. Two-hour fire-rated wall and
floor assemblies are required between units in multifamily buildings. The most common method
of achieving the required fire separation is by using drywall or plasterboard. It is a challenge for
designers and builders to use a common detail that satisfies both the fire separation and acoustic
insulation requirements (i.e., STC). For example, while it is easy to achieve the fire separation
requirements, it is usually difficult to achieve the acoustic rating (STC or IIC) in floors of
apartment buildings. Therefore, fire-rated steel assemblies should satisfy both fire and acoustic
requirements to the greatest extent possible.

It is necessary to consider the detail design of walls and floors and in particular the junctions
between elements and the potential effect of penetrations through the lining boards to meet the
requirements for fire and also to achieve the required acoustic performance.

5

Residential Steel Framing – Fire and Acoustic Details

3 Acoustic Characteristics of Cold-Formed Steel
Framing

3.1 Introduction

Acoustic insulation criteria often influence the design of floors and walls in multi-occupancy
dwellings such as townhouses, apartments, assisted living facilities, and hotels. Even in single-
family dwellings it may be necessary (although rarely) to consider some method of sound
reduction (attenuation) between some rooms. Although sound insulation construction will add to
building costs, the expenses of correcting acoustical mistakes usually are several-fold higher. In
addition, complaints from occupants can affect the acceptance and long-term viability of
construction systems. Issues such as flanking transmission can be significant and could reduce
the effectiveness of the overall acoustic rating of a specific structure. A proper detail is one that
provides required fire separation, adequate acoustical insulation, and proper thermal insulation.

Sound and vibration sources are usually associated with speech and noise from normal occupant
activities, such as traffic, music, and mechanical equipment. During sound transmission in
buildings and other structures, some of the sound energy is absorbed or dissipated, some is
reflected from various surfaces, and some is transmitted through the building materials and
furnishings. Builders and designers are usually interested in reducing or eliminating the amount
of sound transmitted through building materials by means of barriers and enclosures, acoustically
absorbent materials, and other materials and systems properly shaped and assembled.

3.2 Fundamentals of Sound Transmission

Sound levels and sound insulation values are expressed in decibels (dB). The dB rating is a
representation of the magnitude of the sound (i.e., measure of the amount of sound transmitted
from one medium to another or from one room to another).

The sound rating of building materials or construction assemblies is typically given in a Sound
Transmission Class (STC). The STC is a rating system used to measure the insulation (or
isolation) of airborne sound provided by a barrier. STC is determined from a sound-transmission-
loss curve obtained from a standardized test of a large-scale specimen. The higher the STC
rating, the more soundproof the construction. Table 3.1 provides typical STC ratings of common
building construction materials.

Sound insulation is an interrelationship between loudness of the source side, the acoustic
performance of the dividing barrier and the background noise level on the receiving side of the
barrier. The background noise plays an important part. Apartments located in quiet suburbs need
higher sound insulation between units than apartments located on busy roads.

Table 3.2 indicates the situation of different noise sources likely to occur in a typical apartment,
and their relative audibility for a typical suburban background noise level of 40 dB. This relates
to 30 dB background in the apartment with the windows open.
6

Residential Steel Framing – Fire and Acoustic Details

Table 3.1 - STC of Various Construction Materials
Building Component STC
¼-inch plate glass 26
¾-inch plywood 28
½-inch gypsum board, both sides of 2x4 studs 33
¼-inch steel plate 36
Concrete block: Autoclaved aerated 45
3-inch concrete wall 47
6-inc Reinforced concrete slab (4-1/8” thick) 44
6-inch concrete block wall 42
8-inch reinforced concrete wall 51
12-inch concrete block wall 53
12-inch Brick 56
2x4 wood studs (16” o.c.) with 1/2” GWB both sides 33-39
1-5/8 inch steel studs (24” o.c.) with 1/2” GWB both sides 39
3-5/8 inch steel studs (24” o.c.) with 5/8” GWB both sides 40-44
3-5/8 inch steel studs (24” o.c.) with 1/2” GWB both sides 39
Source: Australian Building Code Board [8], HUD Report [9], LGSEA [10].
For SI: 1 inch = 25.4 mm

Table 3.2 - Comparative Performance of Sound Insulation for an Ambient Noise
Level of 30dB
STC (dB) Value Using Steel-Framed Assemblies
Type of Noise

40 45 50 55 60
Normal Speech Audible Just audible Not audible - -
Raised Speech Clearly audible Audible Just audible Not audible -
Dinner
Party/Laughter
Clearly audible Audible Just audible Not audible Not audible
Shouting Clearly audible Clearly audible Audible Just audible Not audible
Small
Television/Small
Entertainment
System
Clearly audible Clearly audible Audible Just audible Not audible
Large
Television/Large
Entertainment
System
Clearly audible Clearly audible Clearly audible Audible Just audible
DVD with
Surround Sound
Clearly audible Clearly audible Clearly audible Audible Audible
Digital
Television with
Surround Sound
Clearly audible Clearly audible Clearly audible Audible Audible
Source: Australian Building Code Board [8].
7

Residential Steel Framing – Fire and Acoustic Details

There are three types of sound transmission:

Airborne Sound Transmission between rooms can be measured by generating a steady sound of
a particular frequency in one room (source room) and comparing it with sound pressure level in
an adjacent room (receiving room). The level difference is simply the difference between the
source and the receiving levels. However, the level difference is influenced by the acoustic
absorption in the receiving room. This is measured by the reverberation time (the time taken for
a reverberant noise to decay by 60 dB).

Impact Sound Transmission tends to be most relevant for floors. It arises from a variety of
sources, most notably the movement of people within a building, but also from such things as the
slamming of doors. A standard impact sound source (tapping machine) is used to strike the floor
and the impact sound pressure level is measured in the room below. Measurements in a building
can be standardized to a reverberation time of 0.5 seconds, giving the Standardized Impact
Sound Pressure level.

Structure-Borne Sound Transmission occurs when building elements (walls, floors) are set into
vibratory motion by direct mechanical contact with vibrating sources (such as mechanical
equipment or domestic appliances).

Building regulations typically set out requirements for airborne sound insulation of walls
between dwellings (separating walls), and both airborne sound insulation and impact sound
transmission for floors between dwellings (separating floors). Structure-borne sound
transmission is not typically addressed in building codes. Reduction in sound transmission from
the airborne and impact sound transmission sources is generally achieved by adopting special
multi-layered construction (such as resilient layers in floors) or introducing additional mass.
Adding resilient layers (such as dense fiberboard) to floors will significantly improve impact
sound transmission.

Transmission of airborne noise from one room to an adjoining room, separated by a continuous
intervening partition, can occur by two routes:

1. directly through the separating structure (direct transmission), and
2. around the separating structure through adjacent building elements (i.e., through other
walls, ceilings and floors, or through corridors adjacent to such rooms) (flanking
transmission).

Flanking and direct transmissions are illustrated in Figure 3.1.

Sound insulation for the flanking and direct transmission are controlled by the following
characteristics:

• Mass
• Sealing
• Isolation

8

Residential Steel Framing – Fire and Acoustic Details

Sound
Source
Flanking Transmission Direct Transmission
Figure 3.1 – Direct and Flanking Transmission

Direct transmission is easy to predict by conducting laboratory tests because it depends on the
properties of the separating walls. On the other hand, flanking transmission, is far more complex
and much more difficult to trace or predict because it is influenced by the building configuration
and orientation. Flanking transmission is usually the more serious offender and commonly
occurs with airborne as well as structure-borne noise.

Sound transmission across solid walls or single skin (one layer) partitions obeys the mass law
principle. The mass law suggests that the sound insulation of a solid element increases by 5 dB
per doubling of mass. The mass law principle, however, does not apply to light frame
construction, which achieves a far better sound insulation than the law would suggest. This
behavior is due to the presence of a cavity and the degree of isolation between the different
layers of construction. The overall performance of a double skin (two layers) partition can
therefore be determined by simply adding together the sound insulation ratings of its constituent
elements, whereas the mass law would have suggested only a 5-dB improvement.

3.3 Methods of Measurement

Humans experience sound at a range of frequencies (high or low pitch), and most sounds are a
mixture of several different frequencies. However, the sound insulation effectiveness of walls
and floors vary with sound vibration frequency and so certain frequencies within any sound are
likely to be attenuated more effectively than others by any given construction. Low frequency
sounds are generally attenuated less than high frequency sounds, particularly in lightweight
constructions. Therefore, sound insulation characteristics of walls and floors are normally
measured at a number of different frequencies across the hearing range, usually 16 bands from
100 Hz to 3150 Hz (one third octave bands). However, there is increasing concern about the
importance of low frequency sound as many typical noise disturbances such as heavy beat music
and traffic noise are strong at the low frequencies. There are some problems with measurement at
low frequencies, but methods that more accurately reflect the low frequency performance of
walls and floors are being increasingly researched.
9

Residential Steel Framing – Fire and Acoustic Details

3.3.1 Single Figure Ratings

Single Figure Rating is widely used in the United States and Europe. This method assigns a
single value (such as STC rating) for a certain assembly. The rating value is derived from
comparing a number of measured test results to a set of reference results (a reference curve) over
a known frequency range (refer to Table 3.1 for typical STC values of certain construction
materials).

3.4.2 Spectrum Adaptation Terms

The shape of the reference curves used in the single figure ratings reflects the way sound is
perceived by the human ear. However, the Europeans introduced Spectrum Adaptation Terms to
take into account different spectra of noise (living activity and traffic noise) and to assess sound
insulation curves with very low values in a single frequency band (the validity of the rating
achieved with the reference curve alone is limited for such cases) [11].

3.3.3 Frequency Ranges

Sound insulation capabilities of walls and floors vary with the frequency of the noise. Sound
transmission from any given construction will be attenuated at certain frequencies more
effectively than others. Recognizing this fact, the Europeans adopted a frequency range that
allows some flexibility in calculation of the spectrum adaptation terms [11].

3.4 Acoustic Characteristics of Cold-Formed Steel Framing

For sound to be transmitted it requires an elastic medium where particles vibrate. The most
common medium is air, but sound is also transmitted through building materials. When airborne
sound is generated, air particles vibrate, and when they encounter stiff building elements they
induce oscillations in these materials that in turn induce oscillations in the air in neighboring
rooms. Impact sound occurs when an impact to a building element induces oscillations within
that element that are transferred into the neighboring air and through other building elements.

Traditionally, acoustic insulation has been associated with high ‘mass’, which reduces the
vibrations that are induced by any given sound energy level. However, this practice is often
inefficient and ill suited for prefabrication and stick-frame steel construction. Lightweight
constructions are designed with a different approach including the use of:

separate layers of mass, •
•
•
•
resilient layers to reduce the transmission of sound between mass layers,
isolation between multiple layers of materials, and
absorbent layers.

Such practices have been shown to provide high levels of sound insulation between dwellings or
rooms.

10

Residential Steel Framing – Fire and Acoustic Details

Layered Construction

30 dB 30 dB
200 mm
Approximately
60 dB
36 dB
Figure 3.2- Schematic Showing the
Principle of Double Layer
Construction with Associated Acoustic
Benefits
8”
Cold-formed steel (light-frame) constructions
provide far better standards of sound insulation than
the mass law would suggest. This is achieved by
separating the layers that make up the element from
each other as far as possible to act independently.
Thus, in separating walls, two parallel stud walls are
often constructed close to each other, which have
minimal structural connection, each with a gypsum
board internal finish. These act to a large extent as
two independent walls and the acoustic separation
can be nearly doubled. Increasing the mass of each
layer by adding additional layers of gypsum (or
plaster) boards will increase mass and so further
improve acoustic insulation.

Figure 3.2 illustrates the importance of acoustic
separation. The acoustic insulation of individual
elements within a double-layer wall tends to combine
together in a simple cumulative linear relationship, as
long as the two layers are largely structurally
separate. The overall performance of a double skin
wall, for instance, can generally be determined by
simply adding together the sound insulation ratings
of its constituent parts. In this way, two
comparatively lightweight walls of say 30-dB sound
reduction can be combined to give acoustically
enhanced wall with a 60-dB sound reduction.
However, the mass law would only suggest a 6-dB
improvement [12].

11


Residential Steel Framing – Fire and Acoustic Details

3.4.1 Separating Walls

A typical cold-formed steel single stud wall has three possible paths for sound transmission
(Figure 3.3).

1
2
3
Figure 3.3 - Sound Transmission Paths Through Cold-Formed Steel Walls
1 Direct transmission
2 Transmission through the region of the stud
3 Flanking transmission.
The most significant problems are generally caused by transmission due to the effect of the studs.
The studs transfer the vibrations in one wall lining directly to the other and thus to the room
beyond. To improve acoustic performance the structural links between the two gypsum board
layers should be reduced so the wall acts as two independent leaves. This can be achieved in a
number of ways:

• Two separate parallel stud walls are often constructed with a small cavity (0.8 to 2 inches)
(20–50 mm) between them. They have minimal structural connection, each with a gypsum
board finish to the room side. The walls act to a large extent as two independent walls and
the acoustic separation can be nearly doubled.
• The studs can be designed to reduce the transfer of sound, which can be achieved by
introducing some resilience within the web or by the detail design of the shape of the stud.
• The connection between the gypsum board lining and the steel can use resilient connections,
which allow some flexibility and reduce sound transmission. The connection can be
achieved by the use of cold-formed resilient steel channels (also called bars) or acoustic
profiles that have a corrugated web and are installed perpendicular to the studs and to which
the gypsum board is attached.

Figure 3.4 shows a typical separating wall, constructed of cold-formed steel, used commonly in
multi-family dwellings.

Increasing the mass of each wall lining by adding additional layers of gypsum board will further
improve acoustic insulation. Other enhancements include acoustic absorbent materials, usually
rock wool, or glass wool within the space between the two leaves or within one or both frames,
and additional sheathing layers on the cavity side of each leaf.

12

Residential Steel Framing – Fire and Acoustic Details

Figure 3.4 - Typical Characteristics of a Double Steel Stud Separating Wall
1. 2 layers of 5/8” gypsum wallboard
2. 3-1/2” deep steel stud at 24” on center
3. 3” thick rock wool insulation between
studs (within one or both leaves)
4. 3/4” clear cavity
5. 3-1/2” steel stud (43 mil thick steel) at
24” on center
6. 3” thick rock wool insulation between
studs (within one or both leaves)
7. 2 layers of 5/8” gypsum wallboard
2
3
4
5
1
6
7

3.4.2 Separating Floors

One or more of the following achieves the required airborne sound insulation in CFS floors:

• structural separation between layers,
• appropriate mass in each layer,
• sound absorbent quilt, or
• minimising flanking transmission at floor-wall junctions.

The different layers of a typical CFS floor are as follows:

Ceiling

Usually one or more layers of gypsum board are fixed to the steel floor joists through resilient
channels (resilient ceiling). The use of resilient channels improves both airborne and impact
sound insulation compared to gypsum boards fixed directly to the joists. However, the resilient
ceiling amplifies the sound pressure levels near the natural resonant frequencies of the floor,
which occur in the range of 25 to 50 Hz. Thus, in general resilient ceilings decrease impact
sound insulation at frequencies below 50 Hz, which are the frequencies generated by walking.

Floor Structure

Cold-formed steel floor joists can be covered with a wood-based board (plywood, OSB or
chipboard), a cement particleboard or reinforced gypsum fiberboard. Alternatively, a profiled
steel deck can be used with a gypsum board laid on top to provide a base for a resilient layer. To
increase mass (and consequently improve performance) a concrete topping of 2 to 2.75 inches
(50 to 70 mm) can be laid on the profiled steel deck. Acoustic absorbent, in the form of mineral
wool, can also be inserted between the steel joists.

13

Residential Steel Framing – Fire and Acoustic Details

Floating Floor

In separating floors, a layer of resilient material, usually in the form of dense mineral wool
insulation (3.75 to 6.25 lb/ft
3
; 60 to 100 kg/m
3
) is usually placed on the structural floor deck and
the finish floor layer of appropriate sheathing material is laid on top. Sometimes a layer of
gypsum board is inserted under or on top of the resilient layer. The effect of the floating floor
can be a 5 to 8 dB improvement in impact sound insulation and also a significant improvement in
airborne sound insulation [13,14,15].

Floor Covering

The improvement in impact sound insulation of soft floor coverings on light CFS floors with a
floating floor is less than for heavyweight CFS floors. Research has shown that soft floor
coverings have a greater impact in filtering out high frequency sound than low frequency sounds
[13,16]. Thus, carpets improve impact resistance for frequencies above about 200 Hz, with
improvements of up to 10 dB at certain frequencies (see Figure 3.5). Overall, the impact sound
rating is improved by about 1.5 dB to 2.5 dB depending on the type of floor covering.
0
10
20
30
40
50
60
70
50 63 80
1
0
0
12
5
16
0
20
0
2
5
0
3
1
5
40
0
50
0
63
0
8
0
0
10
0
0
12
50
16
00
2
0
00
2
5
0
0
31
5
0
40
00
50
00
Frequency (Hz)
Impact sound reduction (dB)
Original (no cover) Carpet Wooden parquet
Figure 3.5 - Impact Sound with Different Surface Layers
Source: Lulea University of Technology [13].

3.4.3 Impact Sound Transmission

Lightweight steel floors can have reduced impact sound insulation performance at low
frequencies compared to heavier floors. Conversely they show better performance at the higher
frequencies. Reduction of impact sound transmission in lightweight steel floors can be achieved
by:

14

Residential Steel Framing – Fire and Acoustic Details

• specifying an appropriate resilient layer with correct dynamic stiffness under imposed
loadings;
• ensuring that the resilient layer has adequate durability; and
• isolating the floating floor surface from the surrounding structure at the floor edges. This
can be achieved by returning the resilient layer up the edges of the walking surface.

Low Frequency Impact Sound

Many site measurements have shown that buildings with lightweight floors can be built to meet
the requirements for acoustic performance (airborne and impact) using the current acoustic rating
methods. However, responses from occupants suggest that low frequency sounds, below 100 Hz,
which are not included in the commonly used acoustic rating methods, are sometimes audible or
felt as non-audible vibrations and have a significant impact on occupant perceptions. Research in
Finland [14] shows that occupant perceptions do not coincide well with the IIC rating and floors
with a good IIC rating may be judged to be unacceptable by occupants.

Walking on a lightweight steel floor generates low frequency “thumps” which are sounds mainly
at frequencies of between 25 and 100 Hz, with peaks occurring at about 32 to 50 Hz. These
frequencies are not represented in the currently used rating methods, and at these frequencies it is
difficult to achieve accurate measurements on site.

Therefore, it is possible that the standard acoustic rating methods do not coincide well with
occupant perceptions with regard to the effects of walking, and that low frequency sounds are not
well represented. There is some debate over what is the proper way to rate low frequencies, and
which of the rating methods is most appropriate. Research in Scandinavia [15,16] concludes that
the opinions of inhabitants about the acoustic performance of lightweight steel floors are based
largely on performance at low frequencies, below 100 Hz. This research suggested that rating
methods that operate from 50 Hz might correspond somewhat better with the subjective ratings
than the rating methods that start at 100 Hz.

15

Residential Steel Framing – Fire and Acoustic Details

4 Building Codes, Classification and Occupancy

4.1 Introduction

A Building Code is a collection of regulations (such as exit sign and smoke detector
requirements), which pertain to specific subjects (such as fire protection systems), which regulate
specific practices (such as designing, constructing or remodeling buildings). Current building
codes provide a process for regulations to reflect current technology in construction methods and
materials.
No matter what the specific subject may be - construction, property maintenance, fire
preventions, or plumbing – All codes have the same purpose: To protect the public's health,
safety and welfare from tragedies due to fire, structural collapse and general deterioration of the
structures (such as homes, schools, stores and manufacturing facilities.). Building codes provide
protection by reducing potential hazards to building occupants and adjoining properties.

4.2 U.S. Building Codes

Building construction in the United States is governed by interrelated codes and standards that
regulate building, plumbing, gas, mechanical, electrical, energy, fire, and other specialized
aspects of building construction. By definition, a building code is a legal document, which sets
forth requirements to protect the public health, safety, and general welfare as related to the
construction and occupancy of buildings and structures. In so doing, codes generally set forth
requirements for structural design, materials, environmental control, fire protection, light and
ventilation, and energy conservation.

While a small number of municipalities (mostly major cities) write and revise their own building
code, most jurisdictions adopt one or more of the national model building codes. These codes,
which are written, maintained, revised, and distributed by the model code organizations, are
adopted by state or local jurisdictions either as written or more commonly with specific
amendments. There are many thousands of individual code jurisdictions in the United States.

Current U.S. model building codes have significant requirements regulating the use of new
building products and systems (such as cold-formed steel). Some of these requirements are fairly
straightforward while others are subject to interpretation. This creates an element of uncertainty
in terms of gaining approval. Different building codes may also have slightly different
requirements for new building materials, products, and systems.

4.2.1 Model Code Organizations

Currently, there are four U.S. national model-building codes that regulate all types of
construction. In addition there are two model codes specifically for residential construction—the
1998 International One and Two-Family Dwelling Code (formerly published by CABO) [3,17]
16

Residential Steel Framing – Fire and Acoustic Details

and, most recently the 2000 International Residential Code (IRC) [4]. Furthermore, some
localities in the United States, in particular large cities such as New York or Los Angeles, have
their own codes that are often stricter than the model building code requirements. The four major
model building code organizations are as follows:

1) The International Conference of Building Officials (ICBO) [18], headquartered in
Whittier, California, publisher of the Uniform Building Code (UBC) and other
Uniform Codes (but not the Uniform Plumbing Code).

2) The Building Officials and Code Administrators International, Inc. (BOCA) [19],
headquartered in Country Club Hills, Illinois, publisher of the BOCA National
Building Code (BNBC) and other National Codes.

3) The Southern Building Code Congress International, Inc. (SBCCI) [20],
headquartered in Birmingham, Alabama, publisher of the Standard Building Code
and other Standard Codes.

4) The International Code Council, Inc. (ICC), whose three members are ICBO, BOCA
and SBCCI, headquartered in Falls Church, Virginia, publisher of the 2000
International Building Code (IBC) [21], the 1998 International One and Two-Family
Dwelling Code, the 2000 International Residential Code (IRC) and other
International codes.

Until recently, the BOCA, SBCCI and ICBO codes tend to be regional in use with the Uniform
Building Code covering the largest part of the country. The 1998 International One and Two-
Family Dwelling Code replaced the widely used 1995 CABO One and Two Family Dwelling
Code.

In recent years the three model building code bodies (BOCA, SBCCI, and ICBO) agreed to
combine their efforts and as a result, the International Building Code (IBC) and the International
Residential Code (IRC) were published early in the year 2000 (see Table 4.1 and Figure 4.1).
The purpose of the newly developed IRC and IBC is to replace the existing model building codes
with one national code for one- and two-family dwellings and one national code for all other
structures.

The National Fire Protection Association (NFPA), located in Quincy, Massachusetts, is presently
developing a competitive set of codes, including building, plumbing, mechanical and fire.

17

Residential Steel Framing – Fire and Acoustic Details

One or more
International Codes
adopted statewide

One or more
International Codes
adopted within state
at local level

Scheduled to
adopt
Figure 4.1 - Geographical Distribution of the I-Codes
(Source: ICC, Falls Church, VA, July 2002, www.intlcode.orrg)

Table 4.1 - International Codes - Adoption by State
State

International
Building Code
International
Fire Code
International
Residential Code
Comments

Alabama L L L Effective January 2003
Alaska X X L
Arizona L L L
Arkansas A A A Effective September 2003
California
Colorado L L L
Connecticut
Delaware L L
District of
Columbia
Florida
Georgia X X X
Hawaii
Idaho X X X
Illinois L L L
Source: International Code Council, Inc. (ICC), Falls Church, VA, July 2002 (www.intlcode.orrg).
A = State wide adoption; X = Effective statewide; L = Adopted by local governments
18

Residential Steel Framing – Fire and Acoustic Details

Table 4.1 - International Codes - Adoption by State (cont.)
State

International
Building Code
International
Fire Code
International
Residential Code
Comments

Indiana X
Iowa L L L
Kansas L* L L
IBC accepted for state except
for school construction
Kentucky X X
Louisiana
Maine L L L
Maryland X X
Massachusetts A A
Michigan X L X
Minnesota
Mississippi L L L
Missouri L L L State buildings only
Montana
Nebraska L L L
Nevada L L L
New Hampshire A L L Effective September 2002
New Jersey
New Mexico L L
New York X X X
North Carolina X X X
North Dakota X L X
Ohio X L X
Oklahoma L L X* Mechanical provisions only
Oregon
Pennsylvania A L A
Rhode Island X
South Carolina X X X
South Dakota X
Tennessee L L L
Texas L L X
Utah X X X
Vermont
Virginia
Washington
West Virginia
Wisconsin X
Wyoming L L
Source: International Code Council, Inc. (ICC), Falls Church, VA, July 2002. (www.intlcode.org)
A = State wide adoption; X = Effective statewide; L = Adopted by local governments

19

Residential Steel Framing – Fire and Acoustic Details

4.2.2 Methods of Approval

In principle, manufacturers of new products systems, or assemblies have several avenues for
gaining building code recognition, although in practice not all methods may be relevant to a
particular situation.

null Evaluation Reports

Evaluation reports are advisory and not mandatory (the local jurisdiction has the final say on
acceptability), however in practice, local building officials rely heavily on these reports in
approving or disapproving the use of specific products or methods in their jurisdiction.

An evaluation report can be submitted under one national code or multiple national codes. The
National Evaluation Service, Inc. (NES) whose membership includes the Building Officials and
Code Administrators, Inc., and SBCCI Public Safety Testing and Evaluation Services, Inc.
(SBCCI PST & ESI), issue evaluation report. Until recently it also included ICBO Evaluation
Service, Inc. (ICBO ES) which now operates independently.

null Consensus Standards

A standard is a prescribed set of rules, conditions, or requirements concerned with classification
of components, materials, processes, systems, performance, etc. The model building codes place
great reliance on the use of standards produced in the private sector. Standards are typically
developed by voluntary consensus standard-writing organizations, by accredited committees, by
trade associations, and by government.

null Technical Suitability of Products Program

The Technical Suitability of Products Program (TSPP) was established by Congress under
Section 521 of the National Housing Act to assure the successful use of building products,
materials, and systems and to make sure that any material, design, or product that is technically
suitable would be available for use in HUD housing programs. The relevant HUD housing
programs include new homes financed with mortgages insured by the Federal Housing
Administration (FHA) or the Veterans Administration (VA).

Technical suitability documents inform HUD Field Offices of Departmental Acceptance of new
or nonstandard building products that are generally not covered by existing standards. TSPPs are
nationwide in scope.

null Structural Engineering Bulletin (SEB)

An Engineering Bulletin is an acceptance document by which HUD accepts a specific
manufacturer’s housing system or subsystem. The two types of engineering bulletins are:

a. Structural Engineering Bulletin (SEB)
b. Mechanical Engineering Bulletin (MEB)

20

Residential Steel Framing – Fire and Acoustic Details

SEBs indicate the structural acceptability of systems or subsystems such as modular housing or
panelized construction for complete housing units, floor, wall or roof systems. Note that while
HUD acceptance offers recognition and legitimacy that may facilitate product acceptance at the
local level, it is not a sure substitute for a model code evaluation. Technically it is only required
for products used in homes financed with FHA- or VA-insured mortgages, a relatively small part
of the market.

•
•
•
•
4.3 Building Classification

BNBC, UBC and SBC building codes classify structures in accordance with their intended use.
Changes were made in the latest editions of the 1997 UBC, 1999 BNBC, and 1999 SBC codes to
align themselves with each other and the 2000 IBC. A separate code for one- and two-family
dwellings and townhouses using prescriptive provisions was also developed by the ICC titled
“International Residential Code” (IRC). The 2000 IRC includes detailed prescriptive provisions
for steel floor framing, steel wall framing, and steel roof framing.

The model building codes generally classify buildings according to occupancy, using types such
as: residential, business, education, institutional, assembly, storage, mercantile, manufacturing,
and hazardous. Within occupancy classifications, codes also consider issues such as whether the
residents are elderly, disabled, or confined. Unprotected wood construction for example is
generally not permitted in such occupancies as theaters with stages, and some institutions.

4.3.1 IBC Use and Occupancy Classification

The 2000 IBC code is used to define building occupancies and construction types in this report.
The 2000 IBC divides buildings into ten Use and Occupancy Classifications with sub-groups
under several of the classifications. The 2000 IBC further classifies buildings based on the type
of construction. It sets limits for building area and number of stories for each use based on the
type of construction with several modifiers based on location on site and fire protection
elements. A summary of the IBC residential building classification is presented here.

Residential Group R (Groups R-1 through R-4)

Includes buildings and portions of buildings used for sleeping accommodations other than
Institutional. Group R has four sub-groups as follows:

R-1: Residential occupancies where the occupants are primarily transient in nature,
such as hotels and boarding houses.
R-2: Residential occupancies containing more than two dwelling units where the
occupants are primarily permanent in nature, such as apartment houses and dormitories.
R-3: Detached one- and two-family dwellings and multiple single-family dwellings
(townhouses) not more than three-stories high (R-3 shall comply with the IRC).
R-4: Buildings for occupancy as residential care/assisted living facilities including
more than five but not more than 16 occupants (limited residential care facilities).

21

Residential Steel Framing – Fire and Acoustic Details

Table 4.2 provides examples of the residential building occupancies based on the classification
as specified in the IBC.

Table 4.2 – Assembly Group Occupancy (Based on 2000 IBC)
(For a complete listing and limitations, refer to Chapter 3 of the IBC)
Use Examples
R-1
Transient residential occupancies: Boarding houses, hotels and motels
R-2
Residential dwellings: Apartment houses, monasteries, dormitories, fraternities and sororities
R-3
Adult or child care facilities for less than 5 persons in buildings that do not contain more than 2 dwellings
R-4
Residential care/assisted living facilities having more than 5 but less than 16 occupants
Source: 2000 IBC Section 302.

4.3.2 Types of Construction

When addressing fire protection requirements for buildings and other structures, building codes
typically include terms such as:

Fireproof,
Protected Noncombustible (e.g., steel framing covered with fire protective materials such
as gypsum board),
Unprotected Noncombustible (e.g., exposed steel framing members),
Fire-Resistive (a term adopted by the National Fire Protection Association to replace
“fireproof”; may be noncombustible, but noncombustible materials are not necessarily
fire resistive).

Each of the above terms is used based on types of construction as specified in the building codes.
The 2000 IBC construction types are summarized in Table 4.3.

Table 4.3 - Types of Construction (2000 IBC)
Building
Construction Type
Description
I
Constructed of building elements that are of noncombustible materials
(combustible materials are permitted in Type I and II buildings in
certain conditions)
II Similar to Type I Buildings
III Buildings with noncombustible exterior walls and any interior walls
IV
Buildings with noncombustible exterior walls and solid or laminated
wood interior elements
V
Buildings with exterior and interior of any material permitted by the
code
22

Residential Steel Framing – Fire and Acoustic Details

5 Fire and Acoustic Code Requirements

5.1 Introduction

Historically, fire is one of the greatest hazards in light-frame residential buildings [22,23].
Building codes in the U.S. have evolved and improved dramatically to protect buildings, their
occupants, and adjoining structures from fire. To accomplish this, building codes require that
buildings of certain size and type, especially those with high fire risks or high occupancies, be
constructed of noncombustible materials such as steel, gypsum, or concrete.

If a fire does break out in a single-family dwelling, the goal is to prevent it from spreading to
adjoining structures while extinguishing it quickly. Load bearing members (such as studs and
joists) should also be able to support loads in a fire so that the building, or a major part of it, does
not collapse prematurely.

Fire-resistance (expressed in units of minutes or hours) is generally required by building codes
for the various elements of construction and is normally a function of the building classification,
occupancy group and other physical characteristics.

Building regulations also prescribe sound insulation levels for buildings and other structures.
Although these sound insulation requirements do not typically apply to individual dwellings
(such as single-family homes), occupiers do expect some level of acoustic privacy between
rooms. Acoustic insulations are normally required between units of multi-family dwellings,
apartments, and other buildings.

It should be recognized that there is a strong relationship between the configuration of floors and
walls for both fire and acoustic insulation requirements. In practice, the more severe of these
requirements controls the design and construction of floors or walls.

5.2 Fire Requirements

The International Building Code (2000 IBC), the Uniform Building Code (1997 UBC), the
Southern Building Code (1999 SBC), and the National Building Code (1999 BNBC) provide the
fire-resistance and acoustic performance rating requirements for new buildings based on the
building occupancy group and construction type. The International Residential Code (2000 IRC),
the ICC International One and Two Family Dwelling Code (1998 IOTFDC) and the 1995 CABO
provide the fire-resistance and acoustic performance rating requirements for one and two family
dwellings and townhomes.

Building codes typically set the acceptable height and area limits of buildings based on the
combustion characteristics of the structures. The discussion below is based mainly on the
provisions of the model codes that regulate combustible-unprotected type of construction.

Exterior Wall Construction – All of the model codes require that exterior walls within short
distance from the property line (typically 3-5 feet (915-1524 mm)) be of one-hour construction.
23

Residential Steel Framing – Fire and Acoustic Details

The rating requirements in some of the codes are for exposure from both sides. However, many
listed assemblies in the building codes are rated for exposure from one side only.

Separation Between Two-Family Dwelling Units – In general, the U.S. model building codes
require that units in two-family dwellings be separated by one-hour fire-resistive walls
continuous to the underside of the roof sheathing (see 2000 IRC Section R321). A fire-resistance
rating of ½ hour is permitted in buildings equipped with an automatic sprinkler system.

Townhouse Separation – Each townhouse is typically considered as a separate building that
requires a one-hour separation wall (for each building), which is continuous from the foundation
to the underside of the roof sheathing, deck, or slab extending the full length of the wall. A single
two-hour wall is permitted with some restrictions. The 1995 CABO, 1998 IOTFDC and the 2000
IRC permit a single two-hour wall if no plumbing, mechanical equipment, ducts, or vents are in
the wall (electrical wiring and metallic electrical outlet boxes are permitted.) Alternatively, the
1995 CABO and 2000 IRC permit each unit to have a separate one-hour wall. The 1999 SBC
allows plumbing, ducts, and wires in a single two-hour wall if materials and methods meet
specific minimum requirements.

Multifamily Building Separation – The 2000 IRC, 1998 IOTFDC and 1995 CABO do not
address multifamily construction. In both the 1999 BNBC and 1997 UBC, “area separation
walls” with a minimum fire-resistance rating of two hours separate multifamily buildings. They
work as follows: Each code stipulates the maximum allowable floor area for a multifamily
building. If the floor area of a planned building exceeds the limits, two-hour fire-rated walls can
be used to subdivide the building into two or more buildings with floor areas that meet the limits.
The SBC requires four-hour rated walls between buildings.

Multifamily Unit Separation – The three major model codes and the 2000 IBC require one-
hour rated floor/ceiling and wall construction between separate dwelling units within a building.
Some codes lower this limit to ½ hour in exchange for a specified sprinkler installation.

Firestopping – Requirements for firestoppings vary among the model codes. Places where
firestopping is commonly required include: concealed spaces in stud walls and partitions, and
furred spaces at the ceiling and floor levels; interconnections between concealed vertical and
horizontal spaces; concealed spaces between stair stringers at the top and bottom of the run; and
at openings around vents, pipes, ducts, chimneys and fireplaces at ceilings and floor levels.

Draft stop – Requirements for draft stops also are varied. A common requirement is for
installation in the concealed spaces of a floor/ceiling assembly with usable space above and
below it, so that the concealed space is divided into approximately equal areas not exceeding
either 1000 or 500 square feet (92.9 or 46.45 m
2
), depending on the code. Draft stop is also
required in some of the codes in attic spaces of multifamily buildings.

It should be noted that the installation of approved residential fire sprinkler systems could affect
some of the above requirements. Further, penetration of fire-rated assemblies like firewalls is
also addressed by the codes, but this is not unique to steel framed structures.

24

Residential Steel Framing – Fire and Acoustic Details

5.2.1 2000 IBC Fire Requirements

null Fire-Resistance Requirements

All buildings (new, altered or extended) are typically classified in one of the five
construction types defined in Section 4.3 of this report. Fire separation requirements are
shown in Table 5.1 for Residential buildings. Fire-resistance ratings of building elements
are shown in table 5.2. Fire-resistance ratings of exterior walls are shown in Table 5.3.

Firewalls (party walls) provide complete separations between attached buildings.
Firewalls are required to have sufficient structural stability under fire conditions to allow
collapse of construction on either side without collapse of the wall for the duration of
time indicated by the required fire-resistance rating. Firewalls can be constructed of any
approved non-combustible materials (exception Buildings of Type V construction).
Portions of buildings are typically individually classified as to use and are completely
separated from adjacent areas by fire barrier walls as shown in Table 5.4.

Table 5.1 - Required Separation Between Dwelling Units (Hours)
a

Use R-1 R-2 R-3 R-4 U
R-1 2 2 2 3 1
R-2 - 2 2 3 1
R-3 - - 2 3 1
b

R-4 - - 2 3 1
b

U - - - - 1
Source: Table 302.3.3 of the 2000 IBC.
a. Private garage shall be separated from the residence and its attic area by means of
minimum ½” (12.7 mm) gypsum board applied to the garage side. Openings from a
private garage directly into a sleeping room are not permitted.
b. Separation is not required between a Group R-3 and Group U carport if the carport is
entirely open on two sides and no occupancy above it.

25

Residential Steel Framing – Fire and Acoustic Details

Table 5.2 – Fire-Resistance Rating Requirements for Building Elements (Hours)
(For detailed information and exceptions, refer to Table 601 of the 2000 IBC)
Type I Type II Type III Type VI Type V
Building Element
A B A
d
B A
d
B HT A
d
B
Structural Frame
a

Including columns, girders, trusses

3
b

2
b

1

0

1

0

HT

1

0
Bearing walls
Exterior
f

Interior

3
3
b

2
b
2
b

1
1

0
0

2
1

2
0

2
1/HT

1
1

0
0
Nonbearing walls and partitions
Exterior
Interior
e

See Table 5.3
Floor construction
Including supporting beams and
joists
2 2 1 0 1 0 HT 1 0
Roof construction
Including supporting beams and
joists
1 ½ 1
c
1
c
0
c
1
c
0 HT 1
c
0
Source: Table 601 of the 2000 IBC.
a. Members of floor and roof panels that are not connected to the columns are considered secondary members and not part
of the structural frame.
b. Roof supports: Fire-resistance ratings of structural frame and bearing walls are permitted to be reduced by 1 hr where
supporting a roof only.
c. See additional requirements and exceptions in IBC Table 601.
d. An approved automatic fire sprinkler system is allowed to be substituted for 1 hr fire-resistance rated construction. This
is not allowed for exterior walls.
e. See 2000 IBC Section 602.4.6 for additional requirements for nonbearing walls in Type IV construction.
f. Not less than the fire-resistance rating on fire separation distance.

Table 5.3 – Fire-Resistance Rating Requirements for Exterior Walls Based on Fire
Separation Distance (Hours)
a
(For detailed information and exceptions, refer to Table 602 of the 2000 IBC)
Fire Separation Distance
(feet)
Type of Construction R
b
U
< 5
c
All 1 1
≥ 5
< 10
I-A
Others
1
1
1
1
≥ 10
< 30
I-A, I-B
II-B, V-B, Others
1
0
1
1
0
1
≥ 30 All 0 0
Source: Table 602 of the 2000 IBC.
a. Load bearing exterior walls are also required to comply with the fire ratings requirements of 2000 IBC Table 6.30.
b. Group R-3 and Group U when used as accessories to Group R-3 are not required to have a fire-resistance rating
where fire separation distance is 3 feet (914 mm) or more.
c. See 2000 IBC Section 503.2 for party walls.
26

Residential Steel Framing – Fire and Acoustic Details

Table 5.4 – Fire Wall Fire-Resistance Ratings
Group Fire-Resistance Rating (hours)
R-1 3
R-2 3
R-3 2
R-4 2
U 3
a

Source: Table 705.4 of the 2000 IBC.
a. Walls shall be not less than 2-hour fire-resistance rated when
separating buildings of Type II or V construction.

null Automatic Sprinkler Systems

Automatic fire sprinkler systems are required as described in Table 5.5 below:

Table 5.5 – Required Automatic Fire Sprinkler (AFS) Per 2000 IBC

Use Requirements
R-1 Required in all buildings. Can be substituted for a residential sprinkler system (NFPA 13R).
R-2 Required in buildings more than 2 stories high or having more than 16 dwelling units. Can be
substituted for a Residential sprinkler system (NFPA 13R) for buildings up to four stories in height.
R-3 Not required. A fire-resistance rating of ½ hour is permitted for two-family dwellings equipped
throughout with an automatic sprinkler system.
R-4 Required in buildings with more than 8 occupants.
U Not required.

27

Residential Steel Framing – Fire and Acoustic Details

5.2.2 BOCA Fire-Resistance Requirements

All buildings (new, altered or extended) are typically classified in one of the five construction
types defined in Section 4.3 of this report. Buildings shall have a fire-resistant rating as shown in
Table 5.6.

Table 5.6 – Fire-Resistive Requirements for Structural Components Per the 1999 BNBC
1
(For detailed information and exceptions, refer to Table 602 of the 1999 BNBC)
Type 1 Type 2 Type 3 Type 4 Type 5 

Noncombustible Noncombustible Ordinary Wood Frame
Protected
(hours)
Protected
(hours)
Unprotected
(hours)
Protected
(hours)
Unprotected
(hours)
Heavy
Timber
(hours)
Protected
(hours)
Unprotected
(hours)
Framing
Member
1A 1A 2B 2B 2C 3A 3B 4 5A 5B
Exterior
Bearing
Walls
4 3 2 1 0 2 2 2 1 0
Interior
Bearing
Walls
4 3 2 1 0 1 0 1 1 0
Floors 3 2 1-1/2 1 0 1 0
(3)
1 0
Roof
(<15’ high)
2 1-1/2 1 1 0 1 0
(3)
1 0
1
The above fire-resistance ratings are based on conditions such as maximum heights and areas. Increases and reductions in these
ratings for specified design considerations are covered in the code.
2
4x6 roof, 6x10 floor, 6x8 col. (roof), 8x8 col. (floor).
3
3” or 4” (76 or 102 mm) set on edge plus 1” (25.4 mm) flooring (or 15/32” plywood) (12 mm).

28

Residential Steel Framing – Fire and Acoustic Details

5.2.3 UBC Fire-Resistance Requirements

All buildings (new, altered or extended) are classified in one of five construction types similar to
the ones defined in Section 4.3 of this report. Buildings elements shall have a fire-resistant rating
as shown in Table 5.7.

Table 5.7 – Fire-Resistive Requirements for Structural Components Per the 1997 UBC
1
(For detailed information and exceptions, refer to Table 600 of the 1997 UBC)
Type I Type II Type III Type IV Type V
Noncombustible (hours) Combustible (hours)
Building
Element
Fire-
Resistive
Fire-
Resistive
1 Hr. N 1 Hr. N
Heavy
Timber
(H.T.)
1 Hr. N
Exterior
bearing
walls
4
Sec.
602.3.1
4
Sec.
603.3.1
1 N 4
Sec. 604.3.1
4
Sec. 602.3.1
4
Sec. 605.3.1
1 N
Interior
bearing
walls
3 2 1 N 1 N 1 1 N
Exterior
non-bearing
walls
4
Sec.
602.3.1
4
Sec.
603.3.1
1
Sec.
603.3.1
N 4
Sec. 604.3.1
4
Sec. 602.3.1
4
Sec. 605.3.1
1 N
Floors and
floor-
ceilings
2 2 1 N 1 N H.T. 1 N
Roofs and
roof ceiling
2
Sec. 602.5
1
Sec.
603.5
1
Sec.
603.5
N 1 N H.T. 1 N
1
N indicates No general requirements for fire-resistance.

29

Residential Steel Framing – Fire and Acoustic Details

5.2.3 SBC Fire-Resistance Requirements

All buildings (new, altered or extended) are classified in one of five construction types similar to
the ones defined in Section 4.3 of this report. Buildings elements shall have a fire-resistance
rating as shown in Table 5.8.

Table 5.8 – Fire-Resistive Requirements for Structural Components Per the 1999 SBC
a
(For detailed information and exceptions, refer to Table 600 of the 1997 SBC)
Fire-Resistance Rating (Hours)
Type IV Type V Type VI
Building Element
Type I Type II Type III
1-Hour
Protected
Unprot.
1-Hour
Protected
Unprot.
1-Hour
Protected
Unprot.
Party and Fire Walls 4 4 4 4 4 4 4 4 4
Interior Bearing Walls
• Supporting columns,
other bearing walls or
more than one floor
• Supporting one floor
only
• Supporting roofs only

4

3

3

3

2

2

2

1

1

1

1

1

NC

NC

NC

1 (b)

1

1

0 (b)

0

0

1

1

1

0

0

0
Interior Non-bearing
Partitions
See Standard Building Code Sections 609.2, 704.1, 704.2, and 705.2
Floor & Floor/ Ceiling
Assemblies
3 2 See 605
H
1 NC 1 0 1 0
Roofs & Roof/ Ceiling
Assemblies
1.5 (c,e) 1 (c,e,f) See 605
H
1 (c,e) NC (c) 1 0 1 0
Bearing Walls and
gable end roof
(f, g)
Exterior Walls
Interior Walls
(0-3’ distance from
common property line)

4
3

3
3

3
3

2
2

1
1

3
3

3
3

1
1

1
1
NC – Non-combustible, H – Heavy Timber Sizes.
a
Refer to Table 600 of SBC for detailed information and exception.

b
Use of combustible construction in interior bearing partitions is limited to building with two floors and roof only.
c
Approved fire-retardant treated wood may be used in buildings not over two stories high..

d
In one-story buildings structural members of heavy timber sizes may be used as an alternate to unprotected structural roof
members.

e
In buildings of Group R occupancies, the roof or roof/ceiling assembly fire-resistance may be omitted where every part of the roof
structural members have a clear height of 20 feet (6096 mm) or more above any floor, mezzanine or balcony..

f
The use of combustible construction of interior bearing partitions is limited to the support of 2 floors and roof.

g
For certain occupancies, the fire rating may be reduced to 1 hr. with automatic sprinkler system.

30

Residential Steel Framing – Fire and Acoustic Details

5.2.4 IRC, CABO and ICC IOTFDC Fire Requirements

Table 5.9 provides a summary comparison between the International Residential Code (2000
IRC), the One and Two-Family Dwelling Code (CABO 1995) and the International One- and
Two-Family Dwelling Code (ICC 1998) fire-resistance requirements.

Table 5.9 – Fire-Resistant Separation Requirements in the IRC, CABO & OTFDC
Building
Element
2000 IRC 1995 CABO/ 1998 IOTFDC
Exterior Wall
Construction
Section R302 requires that exterior walls with a
fire separation less than 3 feet (914 mm) to have
not less than 1-hour fire resistive rating with
exposure from both sides. Projections must not
extend more than 12 in. (305 mm) into areas
where openings are prohibited. Projections
extending into the fire separation distance must
not have less than 1-hour fire resistive
construction on the underside. Exceptions: Tool
and storage sheds, playhouses, and similar
structures are exempt.
Section 302.1 requires exterior walls
located less than 3-feet (914 mm) from
property lines to have not less than 1-hour
fire resistive rating (rated for exposure
from both sides). Projections must not
extend more than 12 in. (305 mm) into
areas where openings are prohibited.
Draft Stop Section R502.12 requires draft stops to be
installed for usable spaces both above and below
the concealed space of a floor/ceiling assembly,
so that the area of the concealed space does not
exceed 1000 square feet (305 m
2
). The draft stop
must divide the concealed space into
approximately equal areas. When the assembly
is enclosed by a floor membrane above and a
ceiling membrane below draft stop must be
provided in floor/ceiling assemblies for the
following conditions:
1. Suspended ceilings under the floor framing.
2. Truss-type open-web or perforated members
floor framed construction.
Section 502.11 indicates that when there
is usable space above and below a
concealed space in a floor/ceiling
assembly, draft stops must be installed so
that the area of the concealed space does
not exceed 1000 square feet (92.9 m
2
).
The draft stop must divide the concealed
space into approximately equal areas. It
must be provided in floor/ceiling
assemblies when:
1. The ceiling is suspended under the
floor framing, or
2. Floor framing constructed with truss-
type open-web or perforated members,
or
3. A floor membrane above and a ceiling
membrane below enclose the
assembly.
Two-Family
Dwelling
Separation
Section R321.1 requires dwelling units in two-
family dwellings to be separated from each other
by wall and/or floor assemblies of not less than
1-hour fire-resistive rating. Fire-resistive floor-
ceiling and wall assemblies must extend to and
be tight against the exterior wall, and wall
assemblies must extend to the underside of the
roof sheathing.
Section 320.1: Dwelling units in two-
family dwellings must be separated from
each other by wall and/or floor
assemblies of not less than 1-hour fire-
resistive rating. Fire-resistive floor-
ceiling and wall assemblies must extend
to and be tight against the exterior wall,
and wall assemblies must extend to the
underside of the roof sheathing.
31

Residential Steel Framing – Fire and Acoustic Details

Table 5.9 – Fire-Resistant Separation Requirements in the IRC, CABO & OTFDC (cont.)
Building
Element
2000 IRC 1995 CABO/ 1998 IOTFDC
Townhouse
Separation
Section R321.2 requires each townhouse to be
constructed as a separate building with a 1-hour
fire-rated wall assembly (separating the units).
Exception: A common 2-hour fire-resistive wall
is allowed if the cavity of the wall does not
contain plumbing or mechanical equipment,
ducts, or vents. Electrical installations are
limited to electrical wires installed in raceways
and electrical outlet boxes.
Section R320.2: Each townhouse must be
constructed as a separate building with a
1-hour fire-rated wall assembly separating
them.
Exception: A common 2-hour fire-
resistive wall is allowed if the cavity of
the wall does not contain plumbing or
mechanical equipment, ducts, or vents.
Electrical installations are limited to
electrical wires installed in raceways and
electrical outlet boxes.
Firestopping
(fireblocking)
Section R602.8 indicates that firestopping must
be installed to cut off all concealed vertical and
horizontal draft openings and form a fire barrier
between stories and between a top story and
roof space. Section R602.8 provides additional
requirements for wood homes (locations of
fireblocking).
Section 602.7 indicates that firestopping
must be installed to cut off all concealed
vertical and horizontal draft openings and
form a fire barrier between stories and
between a top story and roof space.
Section 602.7 provides additional
requirements for wood homes (locations
of fireblocking).

32

Residential Steel Framing – Fire and Acoustic Details

5.3 Acoustical Requirements

Wall and floor-ceiling assemblies separating dwelling units are typically required to provide
sound insulation for walls, and both airborne and impact sound insulation for floor-ceiling
assemblies. Table 5.10 summarizes the minimum STC and IIC requirements as stipulated in the
US building codes.

Table 5.10 - STC and IIC Requirements Selected Codes
STC (FSTC) Requirements
(Air-Borne Sound
Insulation)
IIC Requirements
(Impact Sound
Insulation)
Building
Code
1

Use
Group
1

Code
Reference
Section
Walls Floor/ Ceilings Floor/Ceilings
BOCA [19] R Section 1214.0 45 45 45
UBC
[18]
R Appendix
Chapter 12
Section 1208
50 (45 if
field tested)
50 (45 if field
tested)
50
(45 if field tested)
SBC [20] - - - - -
2000 IBC Dwelling Units Section 1206 50 (45 if
field tested)
50 (45 if field
tested)
50
(45 if field tested)
CABO
[3]
Between
Dwelling Units
Section 320 45 45 45
ICC IOTFDC
[17]
Between
Dwelling Units
Section 320 45 45 45
IRC
[4]
Between
Dwelling Units
or Between
Dwelling Units
and Public or
Service Areas
Appendix K 45 45 45
California
Title 24
[54]
Party Walls and
Between Floors
of Multi-Family
Dwellings
50 (45 if
field tested)
50 (45 if field
tested)
50
(45 if field tested)
1
Use Group R includes all structures in which families or households live, or in which sleeping accommodations
are provided, excluding those classified as institutional occupancies.

33

Residential Steel Framing – Fire and Acoustic Details

5.4 Determination of Fire and Acoustic Ratings

5.4.1 Determination of Fire-Resistance Ratings

The U.S. model building codes, except the UBC, recognize the ASTM E119 [7] test method as
the standard test method to establish the fire rating of assemblies. The UBC cites its own
standard [24]. Code bodies typically accept fire tests conducted by recognized laboratories (such
as Underwriters Laboratories, UL) or organizations (such as Factory Mutual). Table 5.11
summarizes the most widely recognized test methods.

Table 5.11 - Test Methods for Fire-Rated Steel Assemblies
Standard Title Description
ASTM E119
[7]
Standard Test Methods
for Fire Tests of Building
Construction and
Materials
Test methods described in this fire-test-response
standard are applicable to assemblies of masonry units
and to composite assemblies of structural materials for
buildings, including bearing and other walls and
partitions, columns, girders, beams, slabs, and
composite slab and beam assemblies for floors and
roofs. They are also applicable to other assemblies and
structural units that constitute permanent integral parts
of a finished building.
ASTM E814
[25]
Standard Test Method
for Fire Tests of
Through-Penetration Fire
Stops
Applicable to through-penetration fire stops of various
materials and construction. Fire stops are intended for
use in openings in fire-resistive walls and floors that are
evaluated in accordance with Test Methods E119.
Factory
Mutual
[26]
Insulated Wall
Construction
Intended for non-load bearing walls (curtain walls)
having relatively low fire endurance properties and not
intended as hourly rated fire barriers. This test method
can be modified to evaluate the performance of partition
walls.
Factory
Mutual
[27]
Insulated Steel Deck
Roofs
Intended for the evaluation of commercial type
construction such as steel trusses.
International
Standard ISO
834
[28]
Fire-resistance Tests of
Elements in Building
Construction
Provides the means to evaluate structural elements of
building construction (walls, partitions, columns, beams,
and floors) during a predetermined fire test exposure.
The assemblies are assigned ratings based upon the
duration of the test and the ability of the assembly to
exhibit fire-resistance properties

UBC
Standard 7-1
[24]
Standard for Fire Tests
of Building Construction
and Materials
This test method is based on ASTM E119.
34

Residential Steel Framing – Fire and Acoustic Details

Table 5.11 - Test Methods for Fire-Rated Steel Assemblies (cont.)
Standard Title Description
UL Standard
UL 1479
[29]
Fire Tests of Through-
Penetration Firestops
This test method is based on ASTM E814.
UL Standard
UL 263
[30]
Standard for Fire Tests
of Building Construction
and Materials
This test method is based on ASTM E119.
UL Standard
UL 2079
[31]
Tests for Fire-Resistance
of Building Joint
Systems
Used to test joint systems and firestop systems which
are intended to prevent the spread of fire through
openings between or within fire resistive assemblies.
Intertek
Testing
Services /
Warnock
Hersey
BU-606 [32]
Fire Rating &
Certification for Products
& Systems
Test systems (such as wall assemblies, fire doors and
frames, and floor/roof/ceiling) as effective fire barriers
and to determine the surface burning characteristics of
building material, including flame spread, and smoke
developed during exposure to fire.

5.4.2 Determination of STC and IIC Ratings

The U.S. model building codes recognize the ASTM E90 [33] test method as the standard
method for determining the STC rating for an assembly. Table 5.12 summarizes the most widely
recognized test methods.

Table 5.12 - Test Methods for Acoustical Insulation
Standard Title Description
ASTM E90
www.astm.org
[33]
Standard Test Method for
Laboratory Measurement of
Airborne Sound Transmission
Loss of Building Partitions and
Elements
This test method covers the laboratory
measurement of airborne sound transmission loss
of building partitions such as walls of all kinds,
operable partitions, floor-ceiling assemblies,
doors, windows, roofs, panels, and other space-
dividing elements.
ASTM E 336
www.astm.org
[34]
Standard Test Method for
Measurement of Airborne
Sound Insulation in Buildings
This test method covers a procedure to determine
the noise reduction between two rooms under
field conditions. The evaluation may be made
including all paths by which sound is transmitted
or attention may be focused only on the dividing
partition. The word “partition” in this test
method includes all types of walls, floors, or any
other boundaries separating two spaces. The
boundaries may be permanent, operable, or
movable.
35

Residential Steel Framing – Fire and Acoustic Details

Table 5.12 - Test Methods for Acoustical Insulation (cont.)
Standard Title Description
ASTM E413
www.astm.org
[35]
Standard Classification for
Rating Sound Insulation
This classification provides methods of
calculating single-number acoustical ratings for
laboratory and field measurements of sound
transmission obtained in one-third octave bands.
The method may be applied to laboratory or field
measurements of the sound transmission loss of
a partition in which case the single-number
ratings are called sound transmission class (STC)
or field sound transmission class (FSTC),
respectively. The method may also be applied to
laboratory and field measurements of the sound
isolation between two spaces, in which case the
single-number ratings are called the noise
isolation class (NIC) or normalized noise
isolation class (NNIC).
ASTM E492
www.astm.org
[36]
Standard Test Method for
Laboratory Measurement of
Impact Sound Transmission
Through Floor-Ceiling
Assemblies Using the Tapping
Machine
This test method covers the laboratory
measurement of impact sound transmission of
floor-ceiling assemblies using a standardized
tapping machine.
International
Standard ISO
140-4
[11]
Acoustics – Measurement of
Sound Insulation in Buildings
and of Building Elements
Part 4 of this standard describes the test method
for field measurements of airborne sound
insulation between rooms and Part 6 describes
the test method for laboratory impact sound
insulation of building elements.

36

Residential Steel Framing – Fire and Acoustic Details

6 Fire and Acoustic Details - Industry Literature

6.1 Introduction

The application of fire and acoustic requirements in residential construction are minimal and
generally only relate to common walls between dwellings. However, in recent years some trends
have occurred to change the scope of the fire and acoustic performance of cold-formed steel
framing as it is being used more in multi-story buildings and apartments. There also has been an
increased acceptance of cold-formed steel framing in commercial applications. Furthermore,
there has been a trend towards increased housing densities. This coupled with changes in
lifestyles has lead to a demand for better sound insulation of dwellings (such as internal walls to
have sound insulation to isolate louder rooms.)

As a result more industry literature is becoming available on:

• fire performance of cold-formed steel framed wall systems in both load bearing and non-
load bearing applications. Information about she fire performance of cold-formed steel
floor systems is, however, more limited.
• acoustic performance of a range of wall and floor systems including STC values in excess
of those required in most building codes, and guides for sound insulation of internal walls
within a dwelling.

6.2 Fire-Rated Assemblies

Design information and details on fire-resistance and fire-ratings of cold-formed steel assemblies
are scarce. However, the Gypsum Association, Underwriters Laboratories, Inc., Factory Mutual,
and Intertek Testing Services (Warnock Hersey) are the main sources of information on this
subject. Other organizations, such as the Brick Institute of America, and the American Iron and
Steel Institute (AISI) have limited information, details, and design information. Table 6.1
contains a detailed list of publications and technical data that are currently available.

37

Residential Steel Framing – Fire and Acoustic Details

Table 6.1 - Summary of Industry Literature
Source of
Information
Title Description
American Iron and
Steel Institute
AISI FT-901
[37]
www.steel.org
Fire-Resistance Ratings of
Load Bearing Steel Stud
Walls With Gypsum
Wallboard Protection
With or Without Cavity
Insulation
• This pamphlet summarizes some AISI tests
of gypsum wallboard-clad load-bearing
steel stud walls.
American Iron and
Steel Institute
(AISI)
[38]
www.steel.org
Fire-Resistance Steel-
Frame Construction
• Provides an overview of fire protection
requirements, methods, and materials.
Rated assemblies are included for both
residential and commercial walls, floors,
and roof decks.
American Iron and
Steel Institute
(AISI) [39]
www.steel.org
Designing Fire Protection
for Steel Trusses
• This publication discusses methods of
protecting three types of truss systems.
Engineering and Research
Digest
• This publication presents information on
UL listed steel stud/brick veneer walls.
Brick Institute of
America [40]
www.bia.org
Technical Notes No. 16B,
Calculated Fire-resistance
• Provides information on steel-frame, brick
veneer wall construction fire ratings.
1-1 Loss Prevention Data
Firesafe Building
Construction and
Materials
1-28 Insulated Steel Deck
1-31 Metal Roof Systems
• Series of data sheets addressing fire-rated
assemblies. While these data sheets are
geared towards commercial and industrial
applications, they also contain some
information applicable to residential
construction.
Factory Mutual
[27] [43]
Specification Tested
Products Guide
• Contains a limited number of fire-rated
light-gauge steel assemblies that were
tested in accordance with ASTM E119.
Gypsum
Association
[42]
www.gypsum.org
Gypsum Systems
Fire-resistance Design
Manual – Sound Control
• Systems in this manual utilize gypsum
products to provide fire-resistance to walls,
partitions, floors, ceilings, roof-ceilings,
columns, beams, girders, and trusses. Fire-
rated assemblies in this manual are
classified in accordance to use and fire-
resistance rating.
• Provides sound transmission class (STC)
ratings of steel walls, partitions, and floor-
ceiling systems that utilize gypsum
products.
38

Residential Steel Framing – Fire and Acoustic Details

Table 6.1 - Summary of Industry Literature (cont.)
Description
Source of
Information
Title
Intertek Testing
Services / Warnock
Hersey [43]
Directory of Listed
Products
• Contains construction details for a wide
variety of fire-rated proprietary steel
floor/ceiling assemblies.
Los Angles
Department of
Building and
Safety [44]
www.ladbs.org
Sound Rated Partitions
and Floor-Ceiling
Construction
• Contains steel and wood fire-rated
assemblies with STC and IIC ratings of 50.
Metal Lath/Steel
Framing
Association
[45]
Technical Bulletin “One-
Hour Floor /Ceiling Fire-
resistance Test” and
“Two-Hour Floor/Ceiling
Fire-Resistance Test”
• These bulletins present the results of
specific fire tests.
National Bureau of
Standards
[46]
www.fire.nist.gov/

Report BMS92
Fire-Resistance
Classifications of Building
Constructions
• Provides an overview of fire protection
requirements, methods, and materials.
Rated assemblies are included for both
residential and commercial walls, floors,
and roofs.
National Bureau of
Standards [47]
www.fire.nist.gov/
bfrlpubs/fire89/art00
4.html
Report TRBM44
Fire-Resistance and Sound
Insulation Ratings for
Walls, Partitions and
Floors
• This document gives the fire-resistance and
sound-insulation ratings of walls, partitions,
and floors. The ratings are applicable to
walls and floors in residential and other
types of buildings.
Owens Corning
[48]
www.owenscorning.
com
Extruded Polystyrene
Insulation Foamular
Commercial Steel Stud
System
• Contains information and construction
details for a proprietary system consisting
of steel framed/brick veneer walls that are
routinely specified in commercial and
multi-family residential construction. The
Foamular Extruded Polystyrene Insulation
is a part of fire-resistance rated steel
framing/masonry veneer, non-load bearing
exterior wall assembly. The system was
tested in accordance with ASTM E119 and
provides a 3-hour fire rating
Underwriters
Laboratories Inc.
(UL)
[49]
www.ul.com

Fire Resistance
Directory—Volumes I and
II
• Contains the most extensive listing of fire-
rated assemblies (Vol. I) and firestop
penetrations (Vol. II). The ratings are
categorized by material and usage. Listed
fire-resistive assemblies were tested in
accordance with ASTM E119.
www.etlsemko.com
39

Residential Steel Framing – Fire and Acoustic Details

Table 6.1 - Summary of Industry Literature (cont.)
Source of
Information
Title Description
US Department of
Housing and Urban
Development (HUD)
[50]
www.huduser.org

Fire Ratings of
Archaic Materials
and Assemblies
• Compilation of fire-ratings from earlier
sources for a wide variety of materials and
assemblies found in buildings from the
nineteenth to the mid-twentieth centuries. It
also provides methods for calculating the fire-
resistance of general classes of archaic
materials and assemblies for which no
documentation can be found.

Table 6.2 summarizes the contents of the Gypsum Association’s Fire-resistance Design Manual.
Table 6.3 provides a summary of the UL’s, Gypsum Association’s, and Factory Mutual’s fire
ratings that are applicable to residential construction.

Table 6.2 - Fire-Resistance Design Manual-Gypsum Systems
Fire Rating System Description
1 Hour 2 Hours
Interior Partitions
b b
Chase Walls
b b
Exterior Walls
b b
Metal Clad Exterior Walls
b b
Party Walls
b
Floor-Ceiling Assembly-Steel Frame-
Concrete Slab
b b
Floor-Ceiling Assembly-Steel Frame-
Wood Floor
b
-
Steel Columns with Metal studs -
b
Beams and Girders
b b

40

Residential Steel Framing – Fire and Acoustic Details

Table 6.3 – Fire Ratings of Tested Cold-Formed Steel Assemblies
Load-Bearing Walls Non load-Bearing Walls Source
1

1-HR 2-HR 1-HR 2-HR
UL
b b b b
GA b b b b
FM
b b b b
HUD - - b b
Floors/Ceilings Roof-Ceilings
1-HR 2-HR 1-HR 2-HR
UL b b b b
GA b b - -
FM b b b b
HUD b b
2
- -
1
UL denotes Underwriters Laboratories Inc.; GA denotes Gypsum Association; FM
denotes Factory Mutual; HUD denotes US Department of Housing and Urban
Development.
2
Listed fire rating is 1-1/2 HR.

6.3 Acoustic Assemblies

Design information and details on sound insulation of steel assemblies are scarce. However, the
Gypsum Association, Factory Mutual, and Intertek Testing Services (Warnock Hersey) are the
main sources of information on this subject. Other organizations, such as the Brick Institute of
America, and the American Iron and Steel Institute (AISI) have limited information, details, and
design information. Table 6.4 contains a detailed list of publications and technical data that are
currently available.

41

Residential Steel Framing – Fire and Acoustic Details

Table 6.4 - Summary of Industry Literature
Source of
Information
Title Description
Engineering and
research Digest
• This publication presents information on UL
listed steel stud/brick veneer walls.
Brick Institute of
America
[40]
www.bia.org

Technical Notes No.
16B, Calculated Fire-
resistance
• Provides information on steel-frame, brick
veneer wall construction fire ratings.
California
Department of Health
Services
[51] 
Catalog of STC and IIC
Ratings for Wall and
Floor/Ceiling
Assemblies
• Provides comprehensive set of sound
transmission class (STC) ratings for steel walls
and floor/ceiling assemblies.
Gypsum Association
[42]

www.gypsum.org/secur
epubs/download.asp
Gypsum Systems
Fire-resistance Design
Manual – Sound Control
• Systems in this manual utilize gypsum products
to provide fire-resistance to walls, partitions,
floors, ceilings, roof-ceilings, columns, beams,
girders, and trusses. Fire-rated assemblies in
this manual are classified in accordance to use
and fire-resistance rating.
• Provides sound transmission class (STC)
ratings of steel walls, partitions, and floor-
ceiling systems that utilize gypsum products.
Johns Manville [52]
www.jm.com
Sound Shield for Steel-
Framed Construction
• STC ratings for single and double layer
partition walls.
Los Angles
Department of
Building and Safety
[44] www.ladbs.org
Doc. No. P/BC 2001-69
Sound Rated Partitions
and Floor-Ceiling
Construction
• Contains steel and wood fire-rated assemblies
with STC and IIC ratings of 50.
North American
Insulation
Manufacturers
Association [53]
www.naima.org
Sound Control for
Commercial and
Residential Buildings
• Contains recommendations for steel and other
assemblies using fiberglass insulation to
provide quality noise control.
US Department of
Housing and Urban
Development (HUD)
[58]
www.huduser.org
Noise Assessment
Guidelines
US Department of
Housing and Urban
Development (HUD)
[59]
www.huduser.org
The Noise Handbook
• These handbooks have been prepared to serve as
a basic reference document for for
implementing HUD’s noise policy. It brings
together in one place all the various reports,
informational papers, and other items that have
been put out by HUD over the past several
years.
US Department of
Housing and Urban
Development (HUD)
[9]
www.huduser.org
A Guide to Airborne,
Impact, and Structure
Borne - Noise Control in
Multifamily Dwellings
• Incorporates a broad range of criteria
appropriate for isolating airborne, impact, and
structure-borne noise associated with residential
construction.
42

Residential Steel Framing – Fire and Acoustic Details

7 Fire-Rated and Acoustic Performance Rated
Details

7.1 Fire Rated Assemblies

Tables 7.1 through 7.3 summarize the fire-rated assemblies that are relevant to residential
construction. A comprehensive list of cold-formed steel fire-resistance assemblies is provided in
Appendix A. The contents of these tables are compiled from the three main sources of
information for fire and acoustic details: UL, Gypsum Association and Factory Mutual.
Appendix B contains a list of Canadian fire-rated assemblies [56].

7.1.1 Walls

Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing
(Not complete construction details; consult original source for detailed information. UL- Underwriters Laboratories, Inc.)
Source Construction Detail Specification
Fire-
Rating
(minutes)
UL U404
• Non-Load Bearing Wall
• 350S162-33 studs @ 16” o.c.
• 5/8” gypsum board on one side
• 1/2” cementitious backer board on
other side
• 3” thick mineral wool batts
60
UL U407

• Non-Load Bearing Wall
• 350S162-18 studs @ 16” o.c.
• ½” cementitious backer board,
ceramic tiles and exterior finish
system on either side
• 3” mineral wool batts
60
43
UL U419

• Non-Load Bearing Wall
• 350S162-18 studs @ 24” o.c.
• 5/8” gypsum board on each side of
wall
60

Residential Steel Framing – Fire and Acoustic Details

Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing (cont.)
ource for detailed info riters Labora (N construct
Source Construction Detail
ot complete ion details; consult original s rmation. UL- Underw tories, Inc.)
Specification
Fire-
• Non-Load Bearing Wall
362S1
44
UL U456
Rating
(minutes)

• 37-33 studs @ 16” o.c.
• 5/8” gypsum board on one side
• 3/8” mineral and fiber board on
other side
• Mineral wool, 3 pcf density
60
UL U457

• Non-Load Bearing Wall
• 362S125-18 studs @ 16” o.c.
• 5/8” gypsum board on one side
• ½” XPS and ½” cementitious backer
board on other side
• 3” batt or blanket insulation
between stud cavity 60
UL U465
UL U495

• Non-Load Bearing Wall
• 362S125-18 studs @ 24” o.c.
• 5/8” gypsum board on each side of
wall
60

Residential Steel Framing – Fire and Acoustic Details

45
Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing (cont.)
(Not complete construction details; consult original source for detailed information. UL- Underwriters Laboratories, Inc.)
Source Construction Detail Specification
Fire-
Rating
(minutes)
• Non-Load Bearing Wall
• 362S125-33 studs @ 24” o.c.
• 5/8” gypsum board on one side of
• halt felt building paper,
yd
fiberglass mesh, 3/32” base coat,
1/16” thick finish coat on other side
• Mineral wool batts for exterior walls
60
wall
No. 15 asp
5/8” gypsum board, 4.5 oz/sq
• 362S125-33 studs @ 24”
• 5/8” faced gypsum board on ea
side (or ¾” faced gypsum board
each side)
tiles on one side
• (2) 5/8” gypsum board on othe
• Batt or blanket insulation in stud
cavity
UL V413

UL V416

• Non-Load Bearing Wall
o.c.
ch
on
60
UL U449

• Non-Load Bearing Wall
• 362S125-18 studs @ 24” o.c.
• 7/16” mineral fiber and ¼” ceramic
r side
(min. density 3.5 pcf)
90

Residential Steel Framing – Fire and Acoustic Details

Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing (cont.)
(Not complete construction details; consult original source for detailed information. UL- Underwriters Laboratories, Inc.,
GA – Gypsum Association)
Source Construction Detail Specification
Fire-
Rating
UL U452

• Non-Load Bearing Wall
• 350S125-33 studs @ 24” o.c.
18 mil resilient channel with ½” •
• de
• d
gypsum board on one side
(2) 1/2” gypsum board on other si
3” Batt or blanket insulation in stu
cavity
90
UL V414

• stic board, metal
brackets for ties, 4” wide brick
veneers w/2” air space between
veneer and foam
• 3-1/2” fiber glass batts (0.8 pcf
density)
• Non-Load Bearing Wall
• 362S162-33 studs @ 16” o.c.
• 5/8” gypsum board on one side of
wall
2” foam pla
180
• Non-Load Bearing Wall
• 362S162-33 studs @ 24” o.c.
5/8” Type X gyps
side of wall
• ½” cementitious board on other si
3” mineral fiber insulation in
46
(minutes)
GA
WP 1035

• um board on one
de
• cavity
60

Residential Steel Fram
Source Construction Detail
ing – Fire and Acoustic Details

47
Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing (cont.)
(Not complete construction details; consult original source for detailed information. GA – Gypsum Association)
Specification
Fire-
Rating
(minutes)
GA
WP 1041

• Non-Load Bearing Wall
o.c.
½”

• 362S162-33 studs @ 24”
• 1/2” Type X gypsum board and
fiber cement board on one side of
wall
• 1/2” Type X gypsum board and ½”
fiber cement board on other side of
wall
60
WP 1082

• Non-Load Bearing Wall
• 362S162-18 studs @ 16” o.c.
• 5/8” Type X gypsum board on each
side o
• 3” mineral fiber insulation in
60
WP 1
• Non-Load Bearing Wall
• 362S162-18 studs @ 16” o.c.
• (2) 1/2” Type X gypsum board on
one side of w
• Furring channels and (2) 1/2” Type
X gypsum on other side of wall
GA

f wall
cavity
GA
470

all
• 3” mineral fiber insulation in cavity
120

Residential Steel Framing – Fire and Acoustic Details

48
Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing (cont.)
(Not complete construction details; consult original source for detailed information. GA – Gypsum Association)
Source Construction Detail Specification
Fire-
Rating
(minutes)
GA
• Non-Load Bearing Wall
• 362S162-33 studs @ 24” o.c.
• 5/8” Type X gypsum board on one
side of wall
½” Ty• pe X gypsum board and ¼”
60
fiber cement board on other side of
wall
WP 8
• Non-Load Bearing Wall
362S162-43
• 5/8” Type X gypsum board on one
EIFS with 4” XPS on oth
• Non-Load Bearing Wall
362S162-43 stud
• (2) 5/8” Type X gypsum board on
one side of wall
• (2) 5/8” Type X gypsum board and
WP 8003

GA
122
• studs @ 16” o.c.
side of wall
• 5/8” Type X gypsum board and
EIFS with 2” XPS on other side
60
GA
WP 8123

• Non-Load Bearing Wall
• 362S162-43 studs @ 24” o.c.
• 5/8” Type X gypsum board on one
side of wall
• 5/8” Type X gypsum board and
er side
60
GA
WP 8202

• s @ 24” o.c.
EIFS with 4” XPS on other side
120

Residential Steel Framing – Fire and Acoustic Details

49
Table 7.1 – Fire-Rated Wall Assemblies – Non Load Bearing (cont.)
(Not complete construction details; consult original source for detailed information. GA – Gypsum Association)
Source Construction Detail Specification
Fire-
Rating
(minutes)
WP 8
• Non-Load Bearing Wall
• 362S162-33 studs @ 16” o.c.
• 5/8” foil-backed gypsum board on
one side of w
• 1/2” gypsum with stucco
FM Wall 1

• Non-Load Bearing Wall
• 362S162-22 studs @ 24” o.c.
h side of
60
• 5/8” gypsum board on eac
wall
• Non-Load Bearing Wall
362S137-22 studs @ 24” o.c.
of wall
GA
250

all
120
FM Wall 7

•
• (2) 5/8” gypsum board on each side
120

Residential Steel Fram
(Not
ing – Fire and Acoustic Details

50
nc.)
Table 7.2 – Fire-Rated Wall Assemblies – Load Bearing
complete construction details; consult original source for detailed information. UL- Underwriters Laboratories, I
Source Construction Detail Specification
Fire-
Rating
(minutes)
UL U432

• Load Bearing Wall
• 350S162-33 @ 24” o.c.
• 5/8” gypsum wallboard on each side
60
UL U434
• Load Bearing Wall
• 350S162-33 @ 24” o.c.
• 5/8” gypsum wallboard on one side
7/8” P• ortland cement plaster over
metal lath on other side
60
UL U440

• Load Bearing Wall
ach
• 350S162-33 @ 24” o.c.
• (2) ½” gypsum wallboard on e
side of wall
60

Residential Steel Framing – Fire and Acoustic Details

51
Table 7.2 – Fire-Rated Wall Assemblies – Load Bearing
(Not complete construction details; consult original source for detailed information. UL- Underwriters Laboratories, Inc.)
Source Construction Detail Specification
Fire-
Rating
(minutes)
• Load Bearing Wall
• 350S125-33 @ 24” o.c.
• 5/8” gypsum wallboard on one side
• Load Bearing Wall
• 350S125-33 @ 16” o.c.
• 5/8” gypsum wallboard on one side
1/2” cementitious board
Load Bearing
UL U460

• 5/8” gypsum. 1” rigid polyiso.
insulation, ½” plywood on other
side
• 3” batts or blankets
60
UL U473

• and 5/8”
gypsum board on other side
• 3” batts or blankets
60
UL U423

• Wall
• 350S162-33 @ 24” o.c.
• (2) 5/8” gypsum wallboard on each
side of wall
• 2” mineral wool batts
120

Residential Steel Framing – Fire and Acoustic Details

Table 7.2 – Fire-Rated Wall Assemblies – Load Bearing
(Not complete construction details; consult original source for detailed information. UL- Underwriters Laboratories, Inc.)
Source Construction Detail Specification
Fire-
Rating
(minutes)
• Load Bearing Interior Wall

60
• 350S125-33 @ 24” o.c.
• 5/8” gypsum wallboard on each side
• Batt insulation
Load Bearing Interior Wall
350S
• (2) 1/2” gypsum wal 90
• Batt insulation
• Load Bearing Exterior Wall
unit, or mineral
fiber board
• (2)-½”gypsum wallboard on fire
side
• Batt insulation
60
• 350S125-33 @ 24” o.c.
• ½” gypsum wall board with
Brick/Stucco, ½” or 5/8”
cementitious backer
Brick/Stucco, ½” or
cementitious backer unit,
fiber board
(2)-5/8”gyps
side
UL U425
52
•
• 125-33 @ 24” o.c.
lboard on each
side
• Batt insulation
• Load Bearing Interior Wall
• 350S125-33 @ 24” o.c.
• (3) 1/2” gypsum wallboard on each
side or (2) layers of 5/8” gypsum
wall board on each side.
120
• Load Bearing Exterior Wall
• 350S125-33 @ 24” o.c.
• ½” gypsum wall board with
5/8”
or mineral
• um wallboard on fire
• Batt insulation
90

• Load Bearing Exterior Wall
• 350S125-33 @ 24” o.c.
• ½” gypsum wall board with
Brick/Stucco, ½” or 5/8”
cementitious backer unit, or mineral
fiber board
• (3)-½”gypsum wallboard on fire
side
• Batt insulation
120

Residential Steel Framing – Fire and Acoustic Details

Table 7.2 – Fire-Rated Wall Assemblies – Load Bearing (cont.)
(Not complete construction details; consult original source for detailed information. GA – Gypsum Association)
Source Construction Detail Specification
Fire-
Rating
(minutes)
• Load Bearing Wall
• 350S162-33 @ 16” o.c.
• ½” cemetitious board
• 5/8” Type X gypsum wallboard
• 4-5/8” batt insulation
60
Load Bearing Wall
• 350S162-33 @
• 5/8” Type X gypsum wallboa
60
• Load Bearing Wall
350S162-33 @ 24” o.c.
(2) ½” Type X gypsum wallboard
on each side
53
GA
WP 1035

GA
WP 1026

•
16” o.c.
rd on
each side of wall
GA
WP 1716

•
•
of wall
120

Residential Steel Framing – Fire and Acoustic Details

7.1.2 Floor

Rated Floor A
sult original source for detailed information.)
ratories c tion)
s
Table 7.3 – Fir ssemblies
, In ., GA – Gypsum Associa
Specifi
UL L524
• 700S162-43
furring ch
• (2) ½” gypsum
bottom with 24 gauge
resilien
• 700S162-43 @ 24” o.c.
e layer)
• 1/2” Type X gypsum
board (face layer) on
bottom
• 5/8” T&G plywood on
top
60
• ½” Type X gypsum
board (bas

e-
(Not complete construction details; con
(UL- Underwriters Labo
Source Construction Detail cation
Fire-
Rating
(minutes)
@ 24” o.c.
• 19/32” plywood on top
• (2) ½” gypsum board on
bottom

60

UL L527

• 938S162-54 @ 24” o.c.
• 3/4” plywood on top with
annels
board on
t channels spaced
at 16” o.c.

90
UL L543

• 800S156-43 @ 19” o.c.
• 23/32” plywood on top
• (2) ½” gypsum board on
bottom connected to
362S125-43 ceiling joists
spaced at 16” o.c.

60
GA
FC 4502

GA
C 4503

• 700S162-43 @ 24” o.c.
• ½” Type X gypsum
board (base layer)
• 1/2” Type X gypsum
board (face layer) on
bottom
• 3/4” T&G plywood on
top
60
F
54

Residential Steel Framing – Fire and Acoustic Details

Table 7.3 – Fire-Rated Floor Assemblies (cont.)
ot complete construction details; consult original source for detailed information.)
(CSCC – Canadian Steel Construction Council, see reference [66])
(N
Source Construction Detail Specification
Fire-Rating
(minutes)
CSCC
NRC764-
FF22
• 800S162-43 @ 16” o.c.
• 19/32” pl
• Steel strap bridging fastened
to d
• B k
every
• In t
channels spaced at 16” o.c.
• (2) ½” Type X gypsum board
on bottom

74
ywood on top
un erside of joists
loc ing with C-shapes
5
th
joist
ver ed resilient hat
0S 62-43 @ 16” o.c.
/3 ” plywood on top
un erside of joists
ing with C-shapes
5
th
joist
5” iber glass batt
sul tion between joists
) ½ Type X gypsum board
ttom
NRC
FF24
62-43 @ 16” o.c.
un erside of joists
loc ing with C-shapes
5
th
joist
ver ed resilient hat
els spaced at 16” o.c.
sul tion between joists
Type X gy
bottom
9
CSCC
NRC764-
• 80 1
• 19 2
• Steel strap bridging fastened
to d
• Block
every
• Inverted resilient hat
channels spaced at 16” o.c.
• 3. f
in a
• (2 ”
on bo

68
50/44
FF23
CSCC
764-

• 800S1
• 19/32” plywood on top
• Steel strap bridging fastened
to d
• B k
every
• In t
chann
• 3.5” fiber glass batt
in a
• (2) ½” psum board
on

6

55

Residential Steel Framing – Fire and Acoustic Details

Table 7.3 – Fire-Rated Floor Assemblies (cont.)
(Not comp mation.) lete construction details; consult original source for detailed infor
(CSCC – Canadian Steel Construction Council, see reference [56])
Source Construction Detail Specification
Fire-Rating
(minutes)
CSCC
NRC764-
FF25

• 800S162-43 @ 16” o.c.

s
t
t
.

• 19/32” plywood on top
• Steel strap bridging
fastened to underside of
joists
• Blocking with C-shape
every 5
th
jois
• Inverted resilient ha
channels spaced at 16” o.c
• 1/2” Type X gypsum board
on bottom
46
CSCC
NRC764-
FF27
• 800S162-43 @ 16” o.c
• 1.5” non-structural con
topping
19/32” plywood on
• Steel strap bridging
fastened to u
joists
Blocking with C-shapes
every 5
th
joist
Inverted resilient hat
channels spaced at 16” o.c.
(2) 1/2” T

60
es

Tables 7.
reside
IIC-rated assemblies
-formed steel sound-rated
van
es re compiled mainly
UL, Gypsum and Factory Mutua
r s eel assemblies.

.
crete
• top
nderside of
•
•
• ype X gypsum
board on bottom

7.2 STC and IIC Rated Assembli
4 through 7.6 summarize the STS and that are rele t to
ntial construction. A comprehensive list of cold assemblies is
provided in Appendix A. The contents of these tabl a from the three main
sources of information for fire and acoustic details: l. Appendix
B contains a list of Canadian STC/IIC ratings [56] fo t

56

Residential Steel Framing – Fire and Acoustic Details

7.2.1 Walls

Table 7.4 – Non-Load Bearing Walls – STC Rating
(Not com nsult original source ation.) plete construction details; co for detailed inform
d STC
” T pe X gypsum ½” Type X
yp X gypsum,
ement board
½” Type
fiber cemen
P1052
” Type
g psum gypsu
P1072 e X gypsum 5
Ty e X gypsum 5/8” Type X gypsum
Ty e X gypsum 5/8” Type X gypsum
X gypsum,
v neer venee
Ty e X gypsum 5/8” Type X gyp
e X gypsu
¼” fiber cem
Ty e X gypsum
7/16”
board
fiber
P1470 350S pe X gy
Furring, (2) ½
P1510
” Type X
g psum
gy
5/8”& ½”T
gy
ntitious, ¼”
(2) ½” type X gy
ceramic tile
X gypsum
Furrin
Source
Stud
Designation
Stu
Spacing
(in.)
Cavity Insulation Interior Cover Exterior Cover

Rating
(dB)
WP1023 362S162 24 2-3/4” glass fiber (2) ½ y gypsum 50-54
WP1041 362S162-33 24 None
½” T e
½” fiber c
X gypsum, ½:
t board
50-54
W 362S 24 3-1/2” glass fiber
(2) 5/8 X
y
(2) 5/8” Type X
m
50-54
W 362S 24 3-1/2” glass fiber 5/8” Typ /8” Type X gypsum 45-49
WP1081 362S 24 3” mineral fiber 5/8” p 45-49
WP1082 362S162-18 16 3” mineral fiber 5/8” p 45-49
WP1121 362S162-33 24 None
½” Type
1/8” fiber cement
e
½” Type X gypsum,
1/8” fiber cement
r
45-49
WP1200 362S162-18 24 None 5/8” p sum 40-44
WP1295 362S162-33 24 None 5/8” Typ m
½” Type X gypsum,
ent board
40-44
WP1296 362S 16 3-1/2” mineral fiber 5/8” p
cement

40-44
W 162-33 24 3” mineral fiber (2) ½” Ty psum
” Type X
gypsum
55-59
W 362S 24 2” glass fiber
(2) 5/8
y
ype X
psum, ¼” or 3/8”
psum
55-59
WP1515 362S162-33 24 3” mineral fiber
½” ceme
psum 55-59
WP1520 350S162-33 24 3” mineral fiber ½” Type
g, (2) ½” Type X
gypsum
55-59
W 362S 24 3-1/2” glass fiber (2) ½” Type X gypsum (2) ½” Type X gypsum 55-59 P1521
W 362S 24 3-1/2” glass fiber
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
gypsum
55-59 P1522
W 3 psum
½” Type X gypsum,
½” cementitious backer
50-54 P1565 62S162-18 16 3” mineral fiber (2) ½” Type X gy
W 350S 16 3” mineral fiber (2 pcf) ¾” Type X gypsum 3/4”Type X gypsum 50-54 P1570
WP1615 250S 24 None (2) ½” Type X gypsum (2) ½” Type X gypsum 45-49
P1625 250S125-33 16 2” mineral fiber (3.4 pcf)
3/8” gypsum lath, ¾”
gypsum sand plaster
3/8” gypsum lath, ¾”
gypsum sand plaster
45-49
P1711 362S 24 None
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
40-44
W
W
gypsum
57

Residential Steel Framing – Fire and Acoustic Details

Table 7.5 – Load Bearing Walls – STC Rating
ot complete construction details; consult original source for detailed information.) (N
Source
Stud
Designation
Spacing Cavity Insulation Interior Cover Exterior Co
Stud
(in.) (dB)
WP1204 350S162-33 24 None (2) m½” Type X gypsu
(2) 5/8” Type X
gypsum
40-44
WP1206 350S162-33 24 None 5/8” Type X gypsum 5/8” Type X gypsum 40-44
3) ½” Type X gypsum (3) ½” Type X gypsum
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
gypsum
Type X gy Type X gy
WP8002 362S162-33 3” 24 mineral fiber batts 5/8” gypsum
5/8” gypsum, ½”
cementitious board
-
WP1711
362S162-18
24
F ull cavity Cocoon
insulation
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
gypsum
58
WP1200 362S162-18 24 1-1/2” Co sulation 5/ 5/ coon in 8” Type X gypsum 8” Type X gypsum 50
sulation
/8&rdquo; Type
gypsum
/8” Typ
gypsum
Johns
Manville
362S
16
2” f ss
(0.75 pcf)
ibergla
½” gypsum board ½” gypsum board 46
Johns
Manville
2 ½” gy oard
362S
16 ” rockwool (2.0 pcf) ½” gypsum board psum b 45

ver
STC
Rating
WP1635 350S162-33 24 None ( 45-49
WP1714 250S125-43 16 None 40-44
WP1716 350S162-33 24 None (2) ½” psum (2) ½” psum 40-44
U419
600S162-18
16
Full cavity Cocoon
in
(3) 5 C (3) 5 e C
65
58

Residential Steel Framing – Fire and Acoustic Details

7.2.2 Floors

Table 7.6 – STC/IIC Rated Floor Assemblies
(Not complete construction details; consult original source for detailed i
(For NAIMA rence [53 [56]
nformation.)
) see refe ]; for CSCC see reference
STC/IIC
B)
Figure 27
• 725S162-43 ” o.c.
T&G plywood
• Carpet and pad
subfloor on top
on top
Steel strap ing
3-1/2” glass
• Resilient ch
insulation

CSCC
NRC764
2
ood o
• ap bridging f o
jois
Blocking with C-shapes every
5
th
joist
lient
spaced at 16” o.c.
• (2) ½” Type X gypsum board
on bottom
44/40
-FF2
• 800S162-43 @ 16” o.c.
• 19/32” plyw
Steel str
n top
astened t
underside of
•
ts
• Inverted resi hat channels

Source Construction Detail Specifications Rating
(d
NAIMA
@ 24
•
• bridg
• fiber
annels
• 5/8” gypsum board on bottom
56/71

CSCC
NRC764
-FF23
• 800S162-43 @ 16” o.c.
• 19/32” plywood on top
• Steel strap bridging fastened to
underside of joists
• Blocking with C-shapes every
5
th
joist
• Inverted resilient hat channels
spaced at 16” o.c.
• 3.5” fiber glass batt insulation
between joists
• (2) ½” Type X gypsum board
on bottom
50/44

59

Residential Steel Framing – Fire and Acoustic Details

Table 7.6 – STC/IIC Rated Floor Assemblies (cont.)
(Not complete construction details; consul riginal source for detailed information.)

t o
(For CSCC see reference [56])
Source Construction Detail Specifications
STC/IIC
Rating
(dB)
CSCC
NRC764
• Steel strap bridging faste
underside of joists
• Blocking with C-shapes
th
5 joist
• Inverted resilient hat channel
spaced at 16” o.c.
• 3.5” fiber glass batt insulation
between joists
b• (2) ½” Type X gypsum
on bottom
52/42
SCC
• 800S162-43 @ 16” o.c.
• 19/32” plywood on top
Steel strap bridging fastened to
underside of joists
Blocking with C-shapes every
th
5 joist
Inverted resilient hat channels
spaced at 16” o.c.
a• 1/2” Type X gypsum bo
bottom
SCC
• 800S162-43 @ 16” o.c.
• 1.5” non-structural concrete
topping
• 19/32” plywood on top
Steel strap bridging fastened to•
•
•
” o.c.
• (2) 1/2” Type X gypsum board
on bottom
60/31
underside of joists
Blocking with C-shapes every
th
5 joist
Inverted resilient hat channels
spaced at 16
-FF24
• 800S162-43 @ 16” o.c.
• 19/32” plywood on top
ned to
every
s
oard

C
NRC764
-FF25
•
•
•
rd on
51/44

C
NRC764
-FF27

60

Residential Steel Framing – Fire and Acoustic Details

8 Summary of Research on Fire Rating and
Acoustic Performance of Cold-Formed Steel
ramin

8.1 Introduction

It is very difficult to summarize all the research S. Private
laboratories working for private industry usually condu of the current research
ustical (sound) performance and fire rating . The list of
s by no means all-inclusive as proprietary research and testing is typically not publicly
available.

8.2 Fire Rating Research Summ y

Cooper, L. Y., Reneke, P. A., “Prototype Model for Simulating Barrier Fire Performance:
CFAST GYPST – For Evaluating Thermal Respons f tud Wall System,”
National Technical Information Service (NTIS). U.S gfield VA.
. Y., Franssen, J. M. “Basis for Using Fire Modeling With 1-D Thermal Analyses of
Barriers/Partitions to Simulate 2-D and 3-D Barrier/Partition Structural Performance in Real
Fires.” Fire Safety Journal, Vo . 33, No. 2, 115-128 e
Abstract:
Computer fire models for simulating compartm require a
mathematical formulation that couples the ther l response of the gases that fill the
compartment and the thermal response of com ns. The fire
environment characteristics calculated by such models can be used to provide input, via thermal
boundary conditions, to an uncoupled thermal-str or simulating and
evaluating the combined thermal/structural perform e objective
a combined analysis would be to determine, through analysis, the structural fire-
e of a barrier/partition design.
Elhajj, Nader, “Fire Rated Assemblies of Cold-Fo e -gauge Steel
Engineers Association (LGSEA) Technical Note No. 42 . 1998.

Gilvary, K. R., Dexter, R. J., “Evaluation of Alternative Methods for Fire Rating Structural
lements.” National Institute of Standards and Technology (NIST) GCR 97-718; ATLSS Report
o. 97-05; pp102. Gaithersburg, MD. June 1997.
Abstract:
A range of computational methods was evaluated for predicting the load capacity of structures
subjected to fire. Results were compared to furnace experiments on loaded steel columns and
concrete filled tubes. Simple calculations are accurate for simple cases such as steel columns at
uniform temperature. Special-purpose finite-element software, SAFIR, was also accurate for
members with nonuniform temperature distributions and/or composite cross-sections. SAFIR
F g
and testing that is going in the U
ct most, if not all,
on aco of cold-formed steel assemblies
research i
ar
e o Gypsum-Panel/Steel-S
. Department of Commerce, Sprin

Cooper, L
l , S ptember 1999.
ent fire environments typically
ma
partment barriers and partitio
uctural computer model f
ance of the barriers/partitions. Th
of such
resistanc

rm d Steel Construction,” Light
0. Washington DC
E
N
61

Residential Steel Framing – Fire and Acoustic Details

simulations of a continuous frame showed that it withstood three times the fire-exposure duration
alternative to

Ingberg, S. H., Mitchell, N. D., “Fire Tests of Wood- and Metal-Framed Partitions,” National
stitut d Technology (NIST). BMS 071; 53 p. May 12, 1941.
etail the test partitions and gives the results of 147 fire-endurance
tudy partitions were of the load-bearing type, and 38 of them were tested under a
onstant working load while exposed to fire. Their fire-resistance limits, depending on the
ating boards applied on each side to 2
plaster. Filling the spaces between
uds with mineral wool increased the fire-resistance appreciably. The fire-resistance limit was
re-exposed facing, as based on the limiting temperature rise on the edges facing the furnace,

d
on the unexposed surface
erned, but the former remained longer as barriers to the spread of fire after such
rmed Steel Studs in Fire Tests.” American Iron and Steel
stitute. Washington DC. 1980.
Iron and Steel
Institute. Washington DC. 1980.
h and Engineering, Society of Fire Protection
Bethesda, MD, 1999.
predicted from column furnace testing. Computational methods could serve as an
the furnace test method for determining fire-resistance ratings.
e of Standards anIn
Abstract:
his report describes in some dT
or fire and hose-stream tests conducted at the National Bureau of Standards. Seventy-eight of the
partitions were of wood or framed with wood studs and faced with wood, wood fiber, or gypsum
boards, or with plasters applied on wood, gypsum, expanded-metal, or wire laths. The others
were of hollow or solid incombustible nonbearing types, most of which were framed with steel
channels and had body or facings of gypsum or Portland cement plaster on metal laths. Most of
he wood-st
c
facings, ranged from 10 min with 1/2-inch wood-fiber insul
hr with 1-inch-thick facings of neat wood-fibered gypsum
st
considered reached when (a) failure under load or passage of flame occurred, (b) the limiting
temperature rise (250ºF average or 325ºF maximum) was reached on the unexposed side, or (c)
cotton waste in contact therewith became ignited. The protection given the wood studs by the
fi
ranged from one-sixth to one-third of the fire-resistance limit of the partition construction as
such. The results with metal-framed hollow partitions differed little from those with wood-stu
partitions having the same facings, insofar as the rise of temperature
was conc
technical end points had been reached. For the solid plaster partitions, 2 to 2 1/2 inch thick, the
range in fire-resistance was from 20 min with Portland cement sanded plaster or mortar to 2 1/2
hr with un-sanded fibered gypsum plaster. Sanded gypsum plasters gave intermediate results.

Klippstein, K H., “Preliminary Study on the Column-Strength of Cold-Formed Steel Studs
Exposed to Elevated Temperatures.” American Iron and Steel Institute. Washington DC. 1978.

Klippstein, K H., “Behavior of Cold-Fo
In

Klippstein, K H., “Strength of Cold-Formed Studs Exposed to Fire.” American

Kodur, V. K. R., et al, “Fire-Resistance Tests on Load bearing Steel Stud Walls,” Proceedings
of Third International Conference on Fire Researc
Engineers,

Milke, J., “Analytical Method for Determining Fire Resistance of Steel members.” The SFPE
Handbook of Fire Protection Engineering, pages 3/88-3/112. Society of Fire Protection
Engineers. Quincy, MA. 1988.
62

Residential Steel Framing – Fire and Acoustic Details

NBS, “Fire-Resistance and Sound-Insulation Ratings for Walls, Partitions, and Floors.” US
Department of Commerce. National Bureau of Standards. Technical Report on Building
Materials TRBM 44. Washington DC. 1944.
Abstract:
In the construction of buildings, particularly those of the residential type, partition, and floo
constructions should provide safety to life from the spread of fire and should r
r
educe transmitted
d objectionable noises to inaudible levels. This paper gives the fire-resistance and
nd
peration of buildings. By considering only the basic properties having a bearing on fire hazard
e
quired for their structural members. In Chapter 1 this classification is outlined and information
ter 2 contains a discussion of the types of restrictions and
mitations generally incorporated in building codes, with particular reference to their application
s housing typical occupancies as a basis for estimation of fire
verity. In Chapter 4 are given available fire-resistance ratings of building constructions and
sounds an
sound-insulation ratings of walls, partitions, and floors. Most of the fire-resistance ratings are
based on tests made at the National Bureau of Standards. Some are based on tests made at
Underwriters' Laboratories or at Ohio State University. All of the sound-insulation ratings are
based on tests made at the National Bureau of Standards. The detailed results of many of the fire
tests of wood- and metal-framed partitions have been published in Building Materials and
Structures Report BMS 71, “Fire Tests of Wood- and Metal-Framed Partitions.” The details of
the sound-insulation tests are given in Building Materials and Structures Report BMS 44, “Sound
Insulation of Wall and Floor Construction”, and Supplement. Since the present objective is to
present information of value in selecting or designing constructions suitable for use as
subdivisions between family units in multiple dwellings, those having fire-resistance ratings of
less than 1/2 hr are not included. The ratings are applicable to walls and floors in other types of
buildings.

NBS, “Fire-Resistance Classifications of Building Constructions.” Report of Subcommittee on
Fire-Resistance Classifications of the Central Housing Committee on Research, Design and
Construction. Building Materials and Structures Report BMS92. National Bureau of Standards.
Washington DC. 1942. (Available from the National Technical Information Services, Order
Number COM-73-10974).
Abstract:
A classification of building construction from the standpoint of fire safety is presented by a
committee of representatives of Federal agencies concerned with the design, construction, a
o
and fire-resistance, four types were found sufficient to cover the whole range of building
construction. Within each type are two or more classes, which are defined by the fire-resistanc
re
given on how it can be applied with reference to the fire severity obtaining for given structural
and occupancy conditions. Chap
li
to the classification of building types herein presented. Chapter 3 gives results of surveys of
combustible contents of building
se
fire-resistance classifications of roofing materials.

63

Residential Steel Framing – Fire and Acoustic Details

8.2 Acoustical Performance Research Summary

“Catalog of STC and IIC Ratings for Wall and Floor/Ceiling Assemblies.” California
nd Insulation of Wall and Floor Construction”. Department of Commerce. National
ureau of Standards. Building Materials and Structures Report BMS 144. Washington DC.
sign Aid for Office Acoustics.” Form & Function, Issue 4. Chicago
Department of Health Services. Local Environmental Health Services Branch. Sacramento,
California.

Elhajj, Nader, “Acoustic Insulation and Sound Transmission in Cold-Formed Steel
Construction”, Light Gauge Steel Engineers Association (LGSEA) Technical Note No. 360.
Washington DC. 1999.

Loney, W., “Effect of Cavity Absorption and Multiple Layers of Wallboard on the Sound
Transmission Loss of Steel-Stud Gypsum Wallboard Partitions.” The Journal of the Acoustical
Society of America: Volume 53, No. 6, 1973.

Meyers, M., de Souza, K., “Residential Steel Framing, Building a Better North American
Home.” Galvatech 1998. Tokyo, Japan.

NBS, “Sou
B

Roller, S.,“Acoustics in Hotels – Technical Feature.” Form & Function, Issue 4. Chicago IL.
1988.

Roller, S., Waropay V. “De
IL. 1986.

Roller, S., “Research Evaluates Role of Density in Acoustical Insulation Performance.” Form &
Function, Issue 2. Chicago IL. 1985.

Shiner, A., “How to Avoid Flanking Sound in your Acoustical Design.” Form & Function, Issue
3. Chicago IL. 1993.

Shiner, A. “Sound Control Construction.” Form & Function, Issue 1. Chicago IL. 1995.

64

Residential Steel Framing – Fire and Acoustic Details

9 Fire and Acoustic Research and Testing
Residential Applications
Needs for
oduction
acturers have done valuable research and testing in the fire and acoustic
reas of cold-formed steel, there is still a considerable amount of work that needs to be done.

ratories and Gypsum Association being the leaders.
owever, limited cold-formed steel assemblies for use in residential applications have been
AREA SEPARATION WALLS
jective would be to develop designs, either through engineering analysis or testing, for
rea separation walls that both can meet the need for one and two hour fire resistance ratings and
at they need to be self-supporting and be able to break away from an adjacent
sidential dwelling(s), as well as having the above noted fire and acoustic characteristics.
ood-framed
uildings can achieve the 1-hr fire rating and
stud wall with 5/8” (16 mm)
ypsum board on each exterior side and a 1-inch
sted assembly that comes close to the wood
ssembly requires additional layers of gypsum
board between the studs. This is costly and labor
intensive.

9.1 Intr

The residential cold-formed steel market is still in its infancy in the United States. Although the
steel industry, universities, government agencies, research institutions and other associated
material and tool manuf
a

9.2 Research Needs
Fire and acoustic testing of cold-formed steel assemblies in the U.S. is generally done by the
private sector with Underwriters Labo
H
tested by these organizations. The following are some needed testing and research projects:

•

The ob
a
the necessary acoustic requirements for residential construction. The unique demands of these
walls is th
re

Currently low-rise multi-family w
b
attains an acceptable acoustical rating by
constructing a double
@ 16” or 24” o.c.
350S162-33/ 550S162- 33
5/8” Type C or X
Gypsum Board with No.
6 Screws
Mechanical Bracing
g
(25.4 mm) air gap in the middle. The only UL
te
a
65

Residential Steel Framing – Fire and Acoustic Details

• MPONENT ADDITIVE METHOD CO

he objective would be the development of an analytical method (e.g. simplified analytical
ethod) for evaluating a construction assembly using cold-formed steel framing. While the
pportunity of such an approach (e.g. Harmathey’s Rule) it was
eveloped using tested assemblies of wood frame construction. As a result, a barrier to the steel
ing
old-formed steel framing.
ASSEMBLY
n of
e ted construction).
ACOUSTIC DATA
ery limited data exist in the U.S. on the IIC ratings of steel floors. Although one could find a
re resistance rated design(s), one cannot find a fire resistance rated design that also has
cceptable acoustical test data for that exact same assembly. Testing is required to expand the
urrent data.
T
m
wood industry has had the o
d
industry is the perception that there could not be a substitution of framing members without
some form of substantiation as to the validity of that approach. The work would require fire
endurance testing, in combination with an analytical analysis of existing fire endurance tests, to
compare and validate the Harmathey Rule component additive method to assemblies contain
c

• TWO-HOUR FLOOR/CEILING

The objective would be the testing and listing of two-hour rated fire resistance floor/ceiling
assemblies containing cold-formed steel framing and wood sheathing. At this time only one such
test has been completed through a joint venture with the Gypsum Association. The barriers that
support the future development in this arena are the lack of available options for cold-formed
teel framing to be used in buildings containing mixed occupancies (e.g. where the separatios
th occupancies requires two-hour ra

oist
Cement Board
Insulation

2” Poured Concrete
Metal Deck

(2)-5/8” Type X Gypsum
Board
Resilient Channel
Jo
J
ist
(2)-5/8” Type x
Gypsum Board
Insulation
Resilient Channel
•

V
fi
a
c
66

Residential Steel Framing – Fire and Acoustic Details

• TRUSSES
here has been widespread concern among the fire service, manufacturing, fire sprinkler and
xterior fire rated walls with stucco finishes are
d .S.
nderwriters Laboratory (UL) fire resistance design
x2x16ga backing, which is the preferential material.

• INTERNATIONAL FIRE AND ACOUSTIC DATA

e is a considerable amount of test data available in other countries on fire and acoustic
performance of cold-formed steel assemblies. It is unfortunate that these tests cannot be accepted
in the US automatically since in all likelihood the test standard used would not be the ASTM
standard. If it were possible to get the different building code bodies to agree on accepting other
test standards, it could open up a much wider range of available assemblies.

• STRENGTH OF COLD-FORMED AT ELEVATED TEMPERATURES

Steel loses its strength and becomes elastic under high temperatures. As a matter of fact steel
loses approximately 40% of its strength at 932 °F (500°C) and 60% at 1,112 °F (600°C).
Although these temperatures are higher than the average temperatures typical steel-framed
members are exposed to during the initial time of a fire (due to the presence of drywall and/or
ther fire-resistance materials), loss of strength is a concern for unfinished basements,
p ngs or fires starting in attics. These concerns are valid and more people
re becoming aware of these facts and issues
r a builder’s guide describing the non-combustibility of steel and highlighting the
importance of adequate insulation and caulking to maintain the STC rating. The guide should be
written in a language for the average builder and consumer.

T
insurance communities regarding the fire performance of construction that relies more for
strength on engineering design than on mass. The concern is for firefighter and occupant safety
and roof or floor collapse. The concern is mainly for single-family residences with steel trusses
and whether cold-formed steel trusses would be susceptible to sudden and unpredictable collapse
when subjected to fire conditions. Guidance is needed on how to deal with light-gauge structures
safely and effectively.

• EXTERIOR WALLS

Gypsum Board
2x2x16G Wire
Foam
350S162-33 @ 24” o.c.
with mid-height bracing
7/8”, 3-Coat
Stucco
E
wi ely used in the southwest region of the U
U
number U434 (2001 edition) provides the fire rating
for such construction details. However the support
system for the stucco in UL design U434 is a paper
backed diamond mesh (expanded steel, min. 3/4
lb./sq.yd. attached to the studs). The diamond mesh
backing is more labor intensive to install than the
5/8” Type X
2

Ther
o
im roperly finished ceili

• GUIDE TO FIRE RESISTANCE OF STEEL FRAMING

A pamphlet o
a
67

Residential Steel Framing – Fire and Acoustic Details

68

Residential Steel Framing – Fire and Acoustic Details

10 References
1 “2001 Steel Framing Alliance Annual Report”. Steel Framing Alliance, Washington DC.
September 2001.
2 “Prescriptive Method for Residential Cold-Formed Steel Framing,” U.S. Department of
Housing and Urban Development (HUD). Washington DC. 1996.
3 One and Two Family Dwelling Code. Council of American Building Officials (CABO),
Falls Church, Virginia. 1997.
4 International Residential Code (IRC). International Code Council, Inc. (ICC), Falls
Church, Virginia. 2000.
5 Sidey, M.P. and Teague, D.P. “Elevated Temperature Data for Structural Grades of
Galvanized Steel.” British Steel (Welsh Laboratories) Report, January 1988.
6 Klippstein K. H., “Strength of Steel Studs Exposed to Fire,” Proceeding of the Fourth
International Specialty Conference on Cold-Formed Steel Structures, Volume II.
University of Missouri – Rolla. 1978.
7 ASTM E119. “Standard Test Methods for Fire Tests of Building Construction and
Materials,” American Society of Testing and Materials, West Conshohocken, PA. 1995.
8 Australian Building Code Board, Regulatory Impact Statement. RD 2001/02. May 2001.
9 “A Guide to Airborne, Impact, and Structure Borne - Noise Control in Multifamily
Dwellings”. U.S. Department of Housing and Urban Development, Washington DC.
HUD, 1968.
10 Elhajj, Nader. “Acoustic Insulation and Sound Transmission in Cold-Formed Steel
Construction.” Light-Gauge Steel Engineers Association (LGSEA) Technical Note No.
360. Washington DC. 1999.
11 “Acoustics – Measurement of Sound Insulation in Buildings and of Building Elements –
Part 4: Field Measurement of Airborne Sound Insulation Between Rooms” and Part 6:
Laboratory Measurements of Impact Sound Insulation of Floors,” International
Organization for Standardization. ISO 140-4. 1998.
12 Digest 337, “Sound Insulation: Basic Principles”, BRE, 1988.
13 Shi, W., Agren, A. “Modeling of Impact Sound Insulation of Lightweight Steel Framing
Floors.” Lulea University of Technology Research Report 2000:01, Finland 2000.
14 “Dry Construction - the Finish Approach,” VTT Technology, Helsinki, Finland. 1999.
15 Sipari, P., “Sound Insulation of Steel Houses”. VTT Building Technology, Proceedings of
the 9
th
Nordic Steel Construction Conference, Helsinki, Finland. June 2001.
69

Residential Steel Framing – Fire and Acoustic Details

16 Sipari, P., Neinonen, R., & Parmanen, J., “Acoustic Properties of Wooden Floor Slabs,”
Center of Finland, 1998.

23
MD, 2000.

26
al. Norwood, MA. 1974.
28 “
29
erials,” ANSI/UL 263,
31 riters
Laboratories Inc. (UL). Northbrook Illinois. 2001.
32 “Fire Rating and Certification for Products and Systems,” Intertek Testing Services, ITS
VTT Technical Research
17 International One and Two Family Dwelling Code. International Code Council, Inc.
(ICC), Falls Church, Virginia. 1998.
18 Uniform Building Code. International Conference of Building Officials (ICBO), Whittier,
California. 1997.
19 National Building Code. Building Officials and Code Administrators International, Inc.
(BOCA), Country Club Hills, Illinois. 1997.
20 Standard Building Code. Southern Building Code Congress International, Inc. (SBCCI),
Birmingham, Alabama. 1999.
21 International Building Code (IBC). International Code Council, Inc. (ICC), Falls Church,
Virginia. 2000.
22 “2000 Fire Loss in the U.S.” National Fire Protection Association. Quincy, MA. 2000.
“Firefighter Fatalities in the United States in 2000” FEMA/United States Fire
Administration (USFA). Emmitsburg,
24 “Fire Tests of Building Construction and Materials,” UBC Standard 7-1, International
Conference of Building Officials, Whittier, California. 1997.
25 ASTM E814, “Standard Test Method for Fire Tests of Through-Penetration Fire Stops.”
American Society of Testing and Materials, West Conshohocken, PA. 2000.
“Factory Mutual System, Insulated Wall Constructions, Approved Class Number 4411”,
Factory Mutu
27 “Factory Mutual System, Class I Insulated Deck Roofs, Approved Class Number 4450”,
Factory Mutual. Norwood, MA. 1989.
Fire-Resistance Tests - Elements of Building Construction,” International Standard for
Standardization ISO 834, 1-16. 1975.
“Fire Tests of Through-Penetrations Fire Stops,” ANSI/UL 1479, Underwriters
Laboratories Inc. (UL). Northbrook Illinois. 2001.
30 “Standard Fire Tests of Building Construction and Mat
Underwriters Laboratories Inc. (UL). Northbrook Illinois. 2001.
“Tests for Fire Resistance of Building Joint Systems,” ANSI/UL 2079. Underw
BU 606, Cortland NY, 1997.
70

Residential Steel Framing – Fire and Acoustic Details

33 ASTM E90, “Standard Test Method for Laboratory Measurement of Airborne Sound
Transmission Loss of Building Partitions and Elements,” American Society of Testing
and Materials, West Conshohocken, PA. 1999.
34 for Measurement of Airborne Sound Insulation in
Buildings,” American Society of Testing and Materials, West Conshohocken, PA. 1997.
35 sification E413-87 (1999) Standard Classification for Rating Sound
Insulation,” American Society of Testing and Materials, West Conshohocken, PA. 1999.
36 aboratory Measurement of Impact Sound
Transmission Through Floor-Ceiling Assemblies Using the Tapping Machine” American
37 “Fire Resistance Ratings of Load Bearing Steel Studs with Gypsum Wallboard Protection
ton DC, 1981.
I).
Washington DC, 1973.
39 merican Iron and Steel Institute. AISI
FT 227-1281-20M-NB, Washington DC, 1981.
40 struction (BIA), 16B, Brick
Institute of America. Reston, VA. June 1991.
41 ry Mutual.
Norwood, MA. 1993.
42 Edition, Gypsum Association (GA). Washington
DC. 2000.
43 ol. I and II,” Intertek Testing Services (ITS).
Cortland, NY. 1997.
44 eiling Construction,” Los Angeles Department of
Building and Safety Document No. P/BC 2001-69. Los Angles California. February
45 “One-Hour Floor/Ceiling Fire-Resistance Test” and “Two-Hour Floor/Ceiling Fire-
46 “Fire-Resistance Classifications of Building Constructions National Bureau of
47 “Fire-Resistance and Sound Insulation Ratings for Walls, Partitions and Floors,” NBS
ASTM E336, “Standard Test Method
ASTM 413, “Clas
ASTM E492, “Standard Test Method for L
Society of Testing and Materials, West Conshohocken, PA. 1996.
with or without Cavity Insulation,” Publication FT-901. American Iron and Steel Institute
(AISI). Washing
38 “Fire-Resistance Steel-Frame Construction,” American Iron and Steel Institute (AIS
“Designing Fire Protection for Steel Trusses,” A
“Calculated Fire-Resistance,” Technical Notes on Brick Con
“Factory Mutual System, Specification Tested Products Guide,” Facto
“Fire-Resistance Design Manual” 16
th
“ITS Directory of Listed Products, V
“Sound Rated Partitions and Floor-C
2002.
Resistance Test,” MLSFA Technical Bulletins. Chicago, Illinois.
Standards,” NBS Report BMS92. National Bureau of Standards. Washington DC. 1942.
Report TRBM44. National Bureau of Standards. Washington DC.
71

Residential Steel Framing – Fire and Acoustic Details

48 “Extruded Polystyrene Insulation Foamular Commercial Steel Stud System”, UC
Industries, Inc., an Owens Corning Company, UCI. Parsippany, New Jersey. 1996.
49 “Fire-Resistance Directory,” Underwriters Laboratories Inc. (UL). Northbrook Illinois.
50 “Fire Ratings of Archaic Materials and Assemblies”. U.S. Department of Housing and
51 “Catalog of STC and IIC Ratings for Wall and Floor/Ceiling Assemblies”. California
52 “Sound Shield for Steel- Framed Construction,” Johns Manville.
53
IMA). Alexandria, VA. December 1997.
ared for the NAHB Research Center, Inc.,
Upper Marlboro, MD. Sep. 2001.
57 rformance of Light Steel Frame Housing,” The Steel Construction
Institute, Document RT888. England. November 2001.
58 and McMahon, N., “Noise Assessment Guidelines.” U.S. Department of
Housing and Urban Development (HUD), Washington DC. February 1972.
59 k.” U.S. Department of Housing and Urban Development (HUD),
Washington DC. 1991-281-930/54016.
2001.
Urban Development (HUD), Washington DC. February 2000.
Department of Health Services, Local Environmental Health Services Branch.
Sacramento, CA.
“Sound Control for Commercial and Residential Buildings.” North American Insulation
Manufacturers Association (NA
54 “Noise Insulation Standard,” California Code of Regulations, Title 24, Part 2, Chapter 2-
35. California
55 “Architectural Graphic Standards,” Seventh Edition. The American Institute of
Architects (AIA), pp 68 and 69.
56 Fox, Steven, “Summary of Fire and Acoustic Building Code Requirements and Solutions
for Residential Steel Framing in Canada,” Prep
“Acoustic and Fire Pe
Schultz, T.
“The Noise Guideboo

72

Residential Steel Framing – Fire and Acoustic Details

Appendix A
t of U.S. Fire- and Sound-Rated Steel Assemblies Lis

Residential Steel Framing – Fire and Acoustic Details

74

Residential Steel Framing – Fire and Acoustic Details

A-1
ceramic tile ceramic tile

Table A1 – UL Non-Load Bearing Walls – Fire-Resistance
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Cavity Insulation Interior Cover Exterior Cover
Fire-
Resistance
U404 350S162-33 24
3” thick mineral wool
batts
5/8” gypsum board
½” cementitious backer
board
1 hr
U405 250S137-18 24 None 5/8” gypsum board 5/8” gypsum board 1 hr
U406 250S131-18 24 2” batt insulation ½” gypsum board ½” gypsum board 1 hr
U407 350S162-18 16 3” mineral wool
½” cementitious backer
board, ceramic tiles,
and exterior finish
system
½” cementitious backer
board, ceramic tiles, and
exterior finish system
1 hr
U409 162S50-43 24 None Metal lath & plaster Metal lath & plaster 1 hr
U419 350S125-18 24 None (1) 5/8” gypsum (1) 5/8” gypsum 1 hr
U442 250S137-18 16 2-1/2” batts or blankets 5/8” gypsum board
½” or 5/8” cementitious
board, ¼”ceramic tiles
1 hr
U456 362S137-33 16 Mineral wool, 3 pcf 5/8” gypsum board
10 mm mineral and
fiber board
1 hr
U457 362S125-18 16 3” batts or blankets 5/8” gypsum board
½” XPS, ½”
cementitious board
1 hr
U465 362S125-18 24 (Optional) batts/blankets 5/8” gypsum board 5/8” gypsum board 1 hr
U468 250S100-18 16/24 2-1/2” glass fiber ½” gypsum board ½” gypsum board 1 hr
U488 250S125-33 16 1” mineral wool batts
3/8” gypsum board,
7/16” plaster
3/8” gypsum board,
7/16” plaster
1 hr
U495 362S125-18 24 Optional 5/8” gypsum board 5/8” gypsum board 1 hr
V409 250S137-18 24 1-1/2” mineral wool batts ½” faced gypsum board ½” faced gypsum board 1 hr
V413 362S125-33 24
Mineral wool batts for
exterior walls only
5/8” paper or vinyl
faced gypsum board
No. 15 asphalt felt
building paper, 5/8”
gypsum board, 4.5 oz/sq
yd fiberglass mesh,
3/32” base coat, 1/16”
thick finish coat
1 hr
5/8” faced gypsum
board
5/8” faced gypsum
board
V416 362S125-18 24 Optional
¾” faced gypsum board ¾” faced gypsum board
1 hr
U449 362S137-33 24
Batts and blankets,
minimum density 3.5 pcf
7/16” mineral fiber, ¼”
ceramic tiles
(2) 5/8” gypsum board 1-1/2 hr
U452 350S125-33 24 3” batts or blankets (2) ½” gypsum board
18 mil resilient
channels, ½” gypsum
board
1-1/2 hr
U471 362S125-18 24
3-1/4” mineral wool batts,
4pcf density
5/8” mineral fiber
board
5/8” mineral fiber board 1-1/2 hr
U403 362S125-18 24
Mineral wool or glass
fiber
2 (5/8”) layers 5/8”
Gypsum, Inner layer
applied w/runner
5/8” gypsum, ½”
gypsum, and 3/8”
gypsum
2 hr
U411 250S125-18 24 None (2) 5/8” gypsum (2) 5/8” gypsum 2 hr
U443 362S125-18 24 3” batts or blankets
½” gypsum board, ½”
cementitious board, ¼”
½” gypsum board, ½”
cementitious board, ¼” 2 hr

Residential Steel Framing – Fire and Acoustic Details

Table A1 – UL Non-Load Bearing Walls – Fire-Resistance (cont.)
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Cavity Insulation Interior Cover Exterior Cover
Fire-
Resistance
U453 350S125-33 24 3” batts or blankets ½” gypsum board
18 mil resilient
channels, (2) ½”
gypsum board,
2 hr
(2) ½” gypsum board
½” cementitious board,
½” gypsum board
U474 362S125-18 16 3” batts or blankets
½” cementitious board,
½” gypsum board
½” cementitious board,
½” gypsum board
2 hr
U495 362S125-18 24 Optional
5/8” classified gypsum
board
5/8” classified gypsum
board
2 hr
U491 350S125-18 24 3” mineral wool batts ¾” gypsum board ¾” gypsum board 2 hr
U493
Double
362S162-43
staggered
16 3-1/2” glass fiber, 0.5 pcf
(2) 5/8” gypsum board,
(2) 5/8” gypsum board
between studs
(2) 5/8” gypsum board,
(2) 5/8” gypsum board
between studs
2 hr
V410 162S125-18 24 Optional
½” faced gypsum
board, ½” laminated
gypsum board
½” faced gypsum board,
½” laminated gypsum
board
2 hr
V412 350S125-18 24 3” mineral wool batts
3/4” faced gypsum
board
¾” faced gypsum board 2 hr
V415 562S162-33 16 3-1/2” mineral wool batts
33 mil furring channels,
2” structural cement
fiber board, 5/8” Type
X gypsum board
33 mil furring channels,
2” structural cement
fiber board, 5/8” Type X
gypsum board
2 hr
24 (3) ¾” gypsum board 3 hr
U408 250S150-18
24
None 1” gypsum board
(4) ¾” gypsum board 4 hr
350S125-18
3” glass fiber or mineral
wool
(1) ¾” gypsum (1) ¾” gypsum 2 hr
162S125-18 None (3) ½” gypsum (3) ½” gypsum 3 hr
U419
250S125-18
24
3” glass fiber or mineral
wool
(2) ¾” gypsum (2) ¾” gypsum 4 hr
U431 362S125-18 16
Spray applied fire
resistive material w/min.
average density of 12 psf
or 24 pcf.
¾” Plaster over metal
lath (18 SWG wire)
¾” Portland cement
plaster over metal lath
(18 SWG wire)
4 hr
(3) ½” gypsum board (3) ½” gypsum board 3 hr
U435 162S125-18 24 Optional
(4) ½” gypsum board (4) ½” gypsum board 4 hr
(2) 5/8” gypsum, (2) 5/8” gypsum, 3 hr
U450 362S125-18 16
Spray applied fire
resistive material w/min.
average density of 12 psf
or 14 pcf.
(3) 5/8” gypsum, (3) 5/8” gypsum, 4 hr
U455 350S125-33 24 3” batts or blankets (3) ½” gypsum board
18 mil resilient
channels, (2) ½”
gypsum board
3 hr

A-2

Residential Steel Framing – Fire and Acoustic Details

Table A1 – UL Non-Load Bearing Walls – Fire-Resistance (cont.)
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Interior Cover Exterior Cover
Fire-
Resistance
250S125-18 1 hr
325S125-25 2
362S125-25
gypsum
e
Cavity Insulation
2”
Spray
re
-3/4” 2 hr
3-1/4”
minimu
(2) 5/8” gypsum board (2) 5/8” board
3 hr
U475
400S125-18
16
applied fi
resistiv
material
w/
m thickness
4”
of:
(3) 5/8” gypsum board
V414 362S162-33
3-1/2” fi ts,

metal brackets for ties,
w/2” air space between
16
ber glass bat
0.8 pcf
5/8” gypsum board 4” wide brick veneers
veneer and foam
3 hr
Table A Gy m Association No oad Bearing Wa ire-Resista
information)
Source
Designation
Stu
Cavity Insulation Interior Cover Exterior Cover
P1015 250S 24 None ” & 5/8” gypsu & 5/8” gypsu 1 hr
P1021 250S 24 3” glass fi ½” Type X gypsum 1 hr
P1023 362S162 24 (2) ½” Type X gypsum ½” Type X gypsum 1 hr
5/8” Type X gypsum
P1041 362S162-33 24 None
½” Type X gypsum,
½” fiber cement board
½” Type X gypsum, ½:
fiber cement board
1 hr
¼” gypsum, ½” Type ¼” gypsum, ½” Type X
gypsum
¼” gypsum, ½” Type
X gypsum
” gypsum, ½” Type X
gypsum
/8” Type X
gypsum
/8” Type X
gypsum
250S None
3/8” gypsum, ½” Type
X gypsum
” Type X gypsum
pe X gy
(3) 5/8” gypsum board
2” foam plastic board,
4 hr

2 – psu n-L lls – F nce
(Not complete construction details; consult original source for more
d
Spacing
(in.)

Stud Fire-
Resistance
Walls and Interior Partitions
W ¼ m ¼” m
W ber (2) ½” Type X gypsum
W 2-3/4” glass fiber
WP1035 362S162-33 16 3” mineral fiber ½” cementitious 1 hr
W
WP1050 250S 24 None

X gypsum

1 hr
WP1051 250S 24 None
¼
1 hr
WP1052 362S 24 None
(2) 5 (2) 5
1 hr
W
3/8” gypsum, ½” Type
X gypsum
P1053 24 1 hr
WP1070 250S 24 1-1/2” mineral fiber ½” Type X gypsum ½ 1 hr
WP1071 250S 24 2” mineral fiber ½” Type X gypsum ½” Ty psum 1 hr
W 5 P1072 362S 24 None 5/8” Type X gypsum 1 hr
½” Type X gypsum ” Type X gypsum
P1076 250S 24 5/8” Type X gypsum /8” Type X gypsum 1 hr
/8” Type X gypsum ype X gy
5/8” Type X gypsum 5/8” Type X gypsum
7/16” gypsum sand
ster, 1/16” lim
7/16” gypsum sand
ster, 1/16” lim
/8” Type X gypsum
WP1073 250S 16 3-1/2” glass fiber ½ 1 hr
W 5 2-3/4” glass fiber
WP1081 362S 24 None 5 5/8” T psum 1 hr
WP1082 362S162-18 16 3” mineral fiber 1 hr
WP1085 250S 16 None
pla e
gauging plaster, 3/8”
Type X gypsum
pla e
gauging plaster, 3/8”
Type X gypsum
1 hr
A-3

Residential Steel Framing – Fire and Acoustic Details

Table A2 – Gypsum Association Non-Load Bearing Walls – Fire-Resistance (cont.)
(N ) ot complete construction details; consult original source for more information
ud
Stud
Spacing
(in.)
24
½” Type X gypsum
Source
St
De on signati
Cavity Insulation Interior Cover Exterior Cover
Fire-
Resistance
WP1090 162S None
¼” gypsum, ½” Type X
gypsum
¼” gypsum, ½” Type X
gypsum
” Type X gypsum
/8” fiber cement
1 hr
WP1121 362S162-33 24 None
,
1/8” fiber cement
veneer
½ ,
1
veneer
P1200 24 None /8” Type X gypsum 1 hr
5/8” Type X gypsum
250S 24 3” glass fi
½” type X gypsum,
ypsum
1 hr
W 5 362S162 5/8” Type X gypsum
WP1201 250S-33 16 None 5/8” Type X gypsum 1 hr
W ber
1/16” veneer 1/16” g veneer
½” type X gypsum,
gypsum
P1240 1 hr
W
pl th pl th
½” gypsum sand
aster, ½” gypsum la
½” gypsum sand
aster, ½” gypsum la
P1290 250S 24 None 1 hr
W P1295 362S162-33 None 5/8” Type X gypsum 1 hr
/8” Type X gypsum
board
162S 24 5/8” Type X gypsum 5/8” Type X gypsum
½” Type X gypsum, ¼”
fiber cement board
16” fiber cemen
24
WP1296 362S 16 3-1/2” mineral fiber 5
7/ t
1 hr
W P1340 None 1 hr
WP1370 250S 24 None ½ er ½” gypsum sand plaster” gypsum sand plast 1 hr
Walls and Interior Partitions (cont.)
W
5/8” gypsum sand
plaster over 3.4 lb.
Metal lath
P1400 162S 15 None
5/8” gypsum sand
plaster over 3.4 lb.
Metal lath
1 hr
24
X gypsum
2 hr
24
½” type X gypsum,
2 hr
glass
(2) 5/8” Type X
5/8”& ½”Type X
gypsum
3” mineral fiber
ceramic tile
½” type X gypsu 2 hr
3” mineral fiber
gypsum
P1521 362S 24 None (2) ½” type X gypsum 2 hr
gypsum
(2) 5/8” Type X
gypsum
P1530 162S 24 None (2) ½” Type X gypsum (2) ½” Type X gypsum 2 hr
None ) ½” Type X gypsum 2 hr
None
(2) 5/8” Type X
gypsum
5/8”Type X gypsu 2 hr
3/32” gypsum veneer
” Type X gypsum
32” gypsum venee
Type X gypsum, ½”
WP1470 350S162-33 3” mineral fiber (2) ½” Type X gypsum
Furring, (2) 1/2” Type
WP1505 250S 2-1/2” glass fiber
½” type X gypsum,
5/8” Type X gypsum 5/8” Type X gypsum
WP1510 362S 24 2” fiber

gypsum

gypsum, ¼” or 3/8” 2 hr
WP1515 24
½” cementitious, ¼”
(2) m362S162-33
WP1520 350S162-33 24 ½” Type X gypsum
Furring, (2) ½” Type X
2 hr
W (2) ½” type X gypsum
WP1522 362S 24 None
(2) 5/8” Type X
2 hr
W
WP1545
WP1546
250S 24 (2 m (2) ½” Type X gypsu
WP1548 250S 24 (2) m
WP1560 250S 24 None
½” Type X gypsum, ½ ,
3/ r
2 hr
WP1565 362S162-18 16 3” mineral fiber (2) ½” Type X gypsum
½”
cementitious backer
2 hr
WP1570 350S 16 3” mineral fiber (2 pcf) ¾” Type X gypsum 3/4”Type X gypsum 2 hr
WP1615 250S 24 None (2) ½” Type X gypsum (2) ½” Type X gypsum 2 hr
A-4

Residential Steel Framing – Fire and Acoustic Details

Table A2 – Gypsum Association Non-Load Bearing Walls – Fire-Resistance (cont.)
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Interior Cover Exterior Cover
.)
N

Cavity Insulation
Fire-
Resistance
Walls and ns (cont Interior Partitio
WP1625 16 Non
gypsum sand plaster gypsum sand plaster
250S125-33 e

½” Type X gypsum, ½”
(2) ½” Type X gypsum 2 hr
(2) 5/8” Type X
gypsum
P1940 250S125-33 None
(2) 5/8” Type X (2) 5/8” Type X
gypsum
2 hr
(3) ½” Ty
162 umS 24 None (2) ¾” Type X gypsum (2) ¾” Type X gyps
24
WP2960
WP2961 None (4) ½” Type X gypsum (4) ½” Type X gypsum
WP2963
162S 24 4 hr
WP2964 250S 24 2” mine r (2pcf) (2 (2ral fibe ) ¾” Type X gypsum ) ¾” Type X gypsum
WP2970 162S 24 None (4) ½” Type X gypsum (4) ½” Type X gypsum 4 hr
Exterior Walls
WP8003 362S162-33 24 None 5/
½” Type X gypsum, ¼”
8” Type X gypsum
fiber cement board
1 hr
WP8004 362S162
minera
5/8” Type X gypsum
7/16” fiber cement
board
1 hr
WP8005 362S 24 None
5/8” Type X glass mat
gypsum
5/8” glass matt gypsum 1 hr
16
3/8” gypsum lath, ¾” 3/8” gypsum lath, ¾”
2 hr
WP1630 250S 24 None (2) ½” Type X gypsum (2) ½” Type X gypsum 2 hr
WP1632 24 one

glass matt gypsum
250S
WP1711 362S 24 None
(2) 5/8” Type X
gypsum
2 hr
W
gypsum
16
WP2800
WP2921
WP2922
WP2924
162S 24 None pe X gypsum (3) ½” Type X gypsum 3 hr
WP2930 3 hr
WP2945 162S None (4) ½” Type X gypsum (4) ½” Type X gypsum 4 hr
4 hr
3-1/2” l fiber
(3.0 pcf)
16
WP8122 362S162-43
EIFS w/2” XPS
5/8” Type X gypsum,
None 5/8” Type X gypsum 1 hr
362S162-43 5/
5/ ,
EIFS w/4” XPS
WP8123 24 None
8” Type X gypsum
1 hr
S162- 24 None
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
sum, EIFS w
XPS
2 hr
WP8205 362S162-33 (
½” Type X gypsum, ½”
16 2) ½” Type X gypsum
cementitious
2 hr
WP8250 362S162-33 3” miner (2 pcf)16 al fiber
5/8” foil-backed
gypsum
½” gypsum, stucco
WP8310 4

(3.86 pcf)
1
a
channel bridging
00S162 16
3” mineral fiber
” gypsum-sand plaster
over 3.4 lb. metal lath
nd 2mil vapor retarder
1” Portland cement
plaster over 3.4 lb.
metal lath & ¾”
2 hr
/4” perlite-portlan
5/8” Type X gypsum 1” perlite plaster
8” Type X gypsum
362 43 gyp /4” WP8202
3” mineral fiber
2 hr
WP8325 362S162-33 16
3-1 d
cement-like back
plaster spray
2 hr
A-5

Residential Steel Framing – Fire and Acoustic Details

Table A2 – Gypsum Association Non-Load Bearing Walls – Fire-Resistance (cont.)
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Cavity Insulation Interior Cover Exterior Cover
Fire-
Resistance
ouble
apart
ineral fi
5/8” Type X gypsum,
5/8” Type
gypsum cross braces
between studs
entitious b
¼” ceramic tiles
WP5015
Double
6.25” apart
5/8” Ty psum,
gypsum cross braces
162S-33, 16 None
pe X gy
9.5” long, Type X
between studs
5/8” Type X gypsum 1 hr
ouble
apart
” mineral fiber
/2” Type X gypsum,
6” long- 1/2” Type X
ypsum cross brace
between studs
½” Type X Gypsum,
½” rd, cementitious boa
¼” ceramic tiles
WP5105
WP5130
Double
162S, 6.25” 16 None
apart
(2) 5/8” Type X
gypsum, 6.25” long,
Type X gypsum cross
braces between studs
(2) 5/8” Type X
gypsum
Movable and Partit Office ions
WP5910 162S 24 None
3/8” gypsum, ½” Type
X gypsum X gypsum
3/8” gypsum, ½” Type
WP6010 2-3/4” fiber glass
WP6020
2” mineral fiber (3.7
pcf)
WP6025
250S 24
2” mineral fiber (3.8
½
7/8” w auge
steel track
½
Al ”
wide, steel
pcf)
” Type X gypsum,
Aluminum battens,
ide, w/ 25 g
” Type X gypsum,
uminum battens, 7/8
w/ 25 gauge
track
/8” Type X gypsum,
Aluminum battens,
/8” wide, w/ 25 gauge
steel track
/8” Type X gypsum,
luminum battens, 7/8”
ide, w/ 25 gauge steel
track
1 hr
pe X gyp
studs
½” Type X gypsum,
um battens over
studs
WP6250 250S 24 None
5/8” um,
A
studs
5/8” Type X gypsum, Type X gyps
luminum battens over Aluminum battens over
studs
1 hr
e X gypsum
” Type X gypsum ” Type X gypsum
Chase Walls
WP6800
25
24 None over 2-1/2” floor & 5/8” Type X gypsum
0S, C-T
studs
1” Type X gypsum
ceiling runners
WP6900
25
studs
¾
over or &
0S, C-T
24 None
” Type X gypsum
2-1/4” flo
ceiling runners
5/8” Type X gypsum 1 hr
studs
1” Type X gypsum
ceiling runners
5/8” Type X gypsum
WP7051
250S, C-T
studs
24 None
1” Type X gypsum
over 2-1/2” floor &
ceiling runners
(2) 1/2” Type X
gypsum
2 hr
WP5005
D
162S-33, 3” 16
1-1/2” m ber for
each stud
6”, X ½” cem oard,
1 hr
WP5070
D
162S-33, 3” 24
1-1/2 for
each stud
1
g s
2 hr
1 hr
1 hr
WP6040 None
WP6130 None
5
7
5
A
w
WP6135 250S 24
2” mineral fiber (2.63
pcf)
½” Ty sum,
Aluminum battens over Alumin 1 hr
WP6254 250S 24
½” Typ in
cavity
½ ½ 1 hr
1 hr
WP7000
250S, C-T
24 None over 2-1/2” floor & 1 hr
A-6

Residential Steel Framing – Fire and Acoustic Details

Table A2 – Gypsum Association Non-Load Bearing Walls – Fire-Resistance (cont.)
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Cavity Insulation Interior Cover Exterior Cover
Fire-
Resistance
250S, C-T
studs
over 4” floor & ceiling
J runners w/H sections
¾” Type X gypsum
WP7125 162S 24 None
(4) 5/8” Type X
gypsum
None 2-hr
¾” Type X gypsum
tween 2-1/4” floor &
ceiling runners
(4) 5/8” Type X
channels
WP7451 250S 24
1” Ty um
bet &
cei rs
(3) X
g None
pe X gyps
ween 2-1/2” floor
ling runne
5/8” Type
ypsum w/ resilient
channels
3 hr
Area Separation Walls
ASW1100 162S 24 None (2) ½” Type X gypsum (2) ½” Type X gypsum 2 hr
ASW110

Table A3 – Factory Mutual Systems -Non-Load Bearing Walls – Fire-Resistance
t comp constructio ls; cons(No lete n detai ult original source for more information)
Source
Stud
esignat
in.)
Cavity Insulation Interior Cover Exterior Cover
Fire-
Wall1
363S
Wall 2 250S137-19 2” mineral 3.0lb/ft)24 wool ( ½” gypsum ½” gypsum 1 hr
None ½” gypsum
l wool (3. gypsum
Wall7 250S137-22 2 N4/30 one 5/8” gypsum 5/8” gypsum 1 hr
½” gypsum
” & ½” gypsum
Wall 20 250S150-27
5/8” gyp anels
between studs
24
sum p
5/8” gypsum 5/8” gypsum 1 hr
Wall 1 362S137-22 N24 one 5/8” gypsum (2) 5/8” gypsum 1/2 h
8” gypsum
16” o.c.
gypsu
mil steel bridging @
16” o.c.
Wall 7 362S137-22 24 None (2) 5/8” gypsum (2) 5/8” gypsum 2 hr
½” gypsu (2) ½” gypsum
WP7053 24 3” mineral fiber (2 pcf)
1” Type X gypsum
2 hr
WP7421 250S 24 None be gypsum w/ resilient 3 hr
5 250S 24 None (2) ½” Type X gypsum (2) ½” Type X gypsum 2 hr

D ion
Stud
Spacing
(
Resistance
362S137-22
162-22
24 None 5/8” gypsum 5/8” gypsum 1 hr
Wall 3 250S137-22 24 ½” gypsum 1 hr
Wall 6 250S137-22 24 2” minera 0lb/ft) ½” gypsum ½” 1 hr
Wall 8 250S137-22 24 2” mineral wool (3.7lb/ft) ½” gypsum 1 hr
Wall 11 250S137-22 24 2” mineral wool (3.0lb/ft) ¼” & ½” gypsum ¼ 1 hr
1- r
Wall 1 250S137-43 24 None
(2) 5/ , 54
mil steel bridging @
(2) 5/8” m, 54
2 hr
Wall 14 250S137-43 24 None (2) m 2 hr
A-7

Residential Steel Framing – Fire and Acoustic Details

Table A4 – UL Load Bearing Walls – Fire-Resistance
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
tud
pacing
n.)
avity Insulation Interior Cover Exterior Cover
Fire-
Resistance
batts
5/8” gypsum board
board
” cementitious backer
rd, ceramic tiles
and exterior finish
system
cementitious back
5/8” gypsum board
5/8” gypsum
laster over metal lath
U440 350S162-33 2 O4 ptional (2) ½” gypsum (2) ½” gypsum 1 hr
5/8” gypsum
” gypsum. 1” rigi
plywood
U472 350S125-33 24 3-1/2” mineral wool batts 5/8” gypsum board
5/8” g ard,
1” polystyrene foamed
plastic board, non-
metallic fabric mesh,
ypsum bo
coating system
U473 350S125-33 16 3” 5/8” gypsum board
½” cem oard,
batts or blankets
entitious b
5/8” gypsum board
U485 350S162-33 1 3
½ ,
6 ” batts or blankets
” cementitious board
5/8” gypsum board
½” cementitious board,
5/8” gypsum board
U487 362S162-33 24
3-1/
6 pcf y
(2) 5/8 oard 5/8” mine er board
2” mineral wool batts,
densit
” gypsum b ral fib
5/8” gypsum
(2) ½” gypsum 1 hr
350S162-43
550S162-43
½” gypsum
½” gypsum w/
aluminum, steel, brick,
stucco, or 7/16”
(1) ½” gypsum (1) ½” gypsum
8” gyps 8” gypone
(2) ½” gypsum (2) ½” gypsum
l wool bat (2) 5/8” gypsum (2) 5/8” gypsum 2 hr
(3) ½” gypsum (3) ½” gypsum 2 hr
U423 350 3 2
N
(2) 3/4” gypsum (2) ¾” gypsum
S162-3 4
one
(2) ½” gypsum 1 hr
2) 5/8” gypsum
(3) ½” gypsum 2 hr
(2) ¾” gypsum
eel siding, brick
mentitious board (16”
d R=3.8)
S
S
(i
C
U404 350S162-33 24
3” thick mineral wool ½” cementitious backer
1 hr
U407 350S162-33 16 3” mineral wool
½
boa ,
½” er
board, ceramic tiles, and
exterior finish system
1 hr
U432 350S162-33 24 Optional 5/8” gypsum board 1 hr
U434 350S162-33 24 Optional
7/8” Portland cement
p
1 hr
U460 350S125-33 24 3” batts or blankets
5/8 d
ployiso. Insulation, ½” 1 hr
1 hr
1 hr
1 hr
1 hr
0.75 hr
U418 or 24 3-1/2” glass fiber batts
(3) fiberboard 2 hr
0.75 hr
(1) 5/ um (1) 5/ sum 1 hr N
1-1/2 hr
2” minera ts
2 hr
(1) 5/8” gypsum 0.75 hr
( 1-1/2 hr
U424 350S162-33 24 Optional
a) ½” gypsum
w/aluminum, vinyl or
st
veneer or stucco.
b) ½” or 5/8”
ce
maximum stud spacing).
c) Foamed plastic (1 pcf
an
2 hr
A-8

Residential Steel Framing – Fire and Acoustic Details

Table A4 – UL Load Bearing Walls – Fire-Resistance (cont.)
(Not complete construction details; consult original source for more information)
Source
ud
Designation
ud
Spacing
.)
avity Insulation Interior Cover Exterior Cover
Fire-
Resistance
½” gypsum
5/8” gypsum
(2) ½” gypsum (2) ½ um ” gyps -1/2 hr
U425
(interior 350S162-33 24
Glass fiber or mineral
wool batts avity
(3) ½”, (2) 5/8” or (2) (3) ½”, (2) 5/8” or (2)
wall)
to fill c
¾” gypsum ¾” gypsum
5/8” gypsum
(2) ½” gypsum
(2) 5/8” gypsum 1/2 h
exterior 35 62-33
r or mi
to fill c
3) ½” or (2) ¾”
st
or 5/8” gypsum w
uminum, steel, brick,
ucco, 7/16” fiberboard
” cementiti
U477 362S1 24
3-1/2” mine l batts,
6 pcf
62-33
ral woo
density
(2) 5/8” gypsum board 5/8” mineral fiber board 2 hr
St
St
(in
C
½” gypsum 0.75 hr
5/8” gypsum 1 hr
1
2 hr
0.75 hr
1 hr
1- r
U425
(
wall)
0S1 24
Glass fibe neral
wool batts avity
(
gypsum
½” /
al

or ½ ous
2 hr
V415 562S162-33 16 3-1/2” mineral wool batts
33 mil furring channels,
2” thick structural
cement fiber board,
33 mil furring channels,
2” thick structural
5/8” Type X gypsum
cement fiber board, 5/8”
Type X gypsum board
board
2 hr
U426 350S162-33 Optional (4) ½” gypsum (4) ½” gypsum 24
U462 350S125-33 24
Op
mineral wool batts)
(4) d (4) d
tional (1” to 3” thick
1/2” gypsum boar 1/2” gypsum boar 3 hr
U530 3 24
1-7/
boa ”
expan
lbs/yd , spray applied
res l
1-7/
boa ”
expan , 2.5
lbs/yd , spray applied
res l
62S175-33 None
32” mineral fiber
rd, ½” by 5/16
ded steel lath, 2.5
2
istive materia
32” mineral fiber
rd, ½” by 5/16
ded steel lath
2
istive materia
4 hr
3 hr
A-9

Residential Steel Framing – Fire and Acoustic Details

Table A5– Gypsum Association Load Bearing Walls – Fire-Resistance
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Cavity Insulation Interior Cover Exterior Cover
Fire-
Resistance
P1035 350S162-33 16 att ins ½” cementitious 1 hr
(2) ½” Type X gypsum (2) 5/8” Type X gypsum
P1206 350S162-33 24 None 5/8” Type X gypsum 5/8” Type X gypsum 1 hr
ype X g (3) ½” Type X gypsum
(2) 5/8” Type X
gypsum
2) 5/8” Type X gypsum
(2) ½” Type X gypsum
P8002 362S162-33 16 mineral fib cementitious boa ” Type X gypsu 1 hr


W 4-5/8”B ulation 5/8” Type X gypsum
WP1204 350S162-33 24 None 1 hr
W
WP1635 350S162-33 24 None (3) ½” T ypsum 2 hr
WP1714 250S125-43 16 None ( 2 hr
WP1716 350S162-33 24 None (2) ½” Type X gypsum 2 hr
W 3” er ½” rd 5/8 m
A-10

Residential Steel Framing – Fire and Acoustic Details

Table A6 – Fire-Resistance of Floor Assemblies
(Not complete construction details; consult original source for more information)
Source
Joist Size/
Designation
Stud
Spacing
(in.)
Cavity Insulation Specifications
re-
esistance
ratories
G533 718S162-43 24
furring channels
Top: 2” l crete w/6x
lded wire fabric and 19/32” corrugated steel
k;
Bott a
bottom
1” mineral wool (8
pcf) on top of
we
dec
ight weight con 6-W1.4xW1.4
om: 26 gauge furring ch nnels, ½” gypsum on
2 hr
G534 718S162-43
Top: 1-1/ concrete w/6x6-
10/10SW fabri
rrugat
ttom ch
bottom
24 None co
Bo
2” light weight
G welded wire
ed steel deck;
c and 19/32”
annels, ½” gypsum on : 26 gauge furring

hr
G537 3
3-1/2” mineral
ins
blown between
ceiling joists
Top: 1-1/2” concrete w/6x6-
1.4 welded wire fabric and 3/8” rib, 3.4
lbs/y
Bot oists spaced at 16”
o.c.
800S156-4 19
wool loose fill
ulation (2.8 pcf)
W1.4xW
light weight
d
2
expanded steel metal lath;
tom: 350S125-43 ceiling j
with ½” gypsum board
hr
nsulation
Top -1/2” light weight co
xW1.4 welded wire fa
2
ded ste
te w/6x6-
ric and 3/8” rib, 3.4
ath;
Diamond mesh m
d steel), spray-ap
h (3.4 lb/sq yd
e resistive
mat rial (2-1/2” plaster)
G802
System
50-1/2
60
500-psi normal weight concrete or lightweight
concr m
on ste ma
rem
The n
with sp istive
1/2”.

Hambro
or None
3
ete (thickness vary fro
el spacing). Concrete
ovable plywood forms or
undersides of concrete a
ray-applied fire res
3” to 4-1/2” based
y be cast over
corrugated steel deck.
d joists are finished
material of 0” to 2-
1 hr- 3 hr
Fi
R
Underwriters Labo
1
1
G704 800S162-43 19
8” glass fiber
i
: 1 ncre
W1.4 b
lbs/yd expan el metal l
Bottom: etal lat
expande plied fir
e
4 hr
L524 700S162-43 24 None
Top: 19/32” plywood or ¾” or 1” floor topping
mixture over 15/32” plywood or ¾” gypsum board
over 19/32” plywood.
Bottom: (2) ½” gypsum board
1 hr
L527 938S162-54 24 None
Top: ¾” plywood on top; Furring channels and
Bottom: 24 gauge, ½” deep resilient channels
spaced at 16” o.c. and (2) 5/8” gypsum board
1-1/2 hr
L543 800S156-43 19
3-1/2” mineral
wool loose fill
insulation (2.8 pcf)
blown between
ceiling joists
Top: 23/32” plywood
Bottom: 362S125-43 ceiling joists spaced at 16”
o.c. with two layers of ½” gypsum board
1 hr

A-11

Residential Steel Framing – Fire and Acoustic Details

Table A6 – Fire-resistance of Floor Assemblies (cont.)
(Not complete construction details; consult original source for more information)
Source
Joist Size/
Designation
Stud
Spacing
(in.)
Cavity Insulation Specifications
re-
esistance
Underwriters Laboratories
oof membrane), insulating concrete (such as
iculite concrete, Cellul concrete, or Perlite
anized corrugated steel roof deck.
: 26 gauge furring
nd two la
annels (2-5/8” wide x
½” gypsum board.
P512 725S175-43
Top:
roof e
hot a 2
and fiber board.
Bottom: Two layers of ½” gypsum board.
24 None
Roof covering (or roof
deck, 2-7/16” thick min
membrane), metal
ral and fiber board,
sphalt or cold tar pitch, -7/16” thick mineral hr
Fi
P511 725S175-43 24 None
Top: Crushed stone at roof covering, roof covering 
(or r
Verm ar
concrete), 1” to 8” thick foamed plastic, and 9/16”
galv
Bottom ch
7/8” deep) a yers of
1 hr
1
P518 800S156-43 24
8” thick glass fiber
insulation installed
between roof joists
Top: Roof covering (or roof membrane), 28 gauge
corrugated steel roof deck (9/16” deep), ½”
gypsum board
Bottom: Bridging and ½” gypsum board.
1 hr
Gypsum Association
FC1145 600S162-43 24
25 gauge corrugated metal deck & 2” light-weight
(105 pcf) concrete on top; ½” Type X gypsum
w/furring channels on bottom
1 hr
FC2116 725S162-43 24 None
28 gauge corrugated metal deck & 2-1/2” concrete
on top; (2) 5/8” Type X gypsum
2 hr
FC4502 700S162-43 24 None
5/8” T&G plywood on top;
(2) 1/2” Type X gypsum on bottom
1 hr
FC4503 600S162-54 24 None
5/8” T&G plywood on top;
(2) 1/2” Type X gypsum on bottom
1 hr
Factory Mutual Systems
FM J.I.
2C9Q7
AC
TJI 24 None
Elastizell concrete, plywood subfloor and two
layers of gypsum ceiling board
1 hr
FM J.I.
2C9Q7
AC
24 None
Corrugated metal deck over steel floor joist,
Elastizell concrete and resilient furring channels
1 hr

R
A-12

Residential Steel Framing – Fire and Acoustic Details

Table A7 – Gypsum Association Non-Load Bearing Walls – STC Rating
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
tud
Spacing
n.)
Cavity Insulation Cover Exterior Cover
STC
Rating
(dB)
er ¼” & 5/8” gypsum ¼” & 5/8” gypsum
1021 250S 4 3” glass fiber 50-
2-3/4” glass fiber (2) ½” Type X gypsum ½” Type X gypsum
½
½” fiber cement board fiber cement board
1050 250S 4 glass f
¼” gypsum, ½” Type ¼” gypsum,
X gypsum X gypsum
50-
¼” gypsum, ½” Type ¼” gypsum, ½” Type
X gypsum X gyp
3-1/2” glass fib r
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
gypsum
3-1/2” glass fiber
3/8” gypsum, ½” Type
X gypsum
3/8” gypsum, ½” Ty
X gypsum
½” Type X gypsum ½” Type X
½” Type X gypsum ½” Type X gypsum
1072 362S 4 -1/2” glass f r 5/8” Type X gypsum 5/8” Type X gyps 45-
r ½” Type X gypsum ½” Type X g
r 5/8” Type X gypsum 5/8” Type X gyps
5/8” Type X gypsum 5/8” Type X gypsu
S162-18 16 5/8” Type X gypsum 5/8” Type X gy
7/16” gypsum sand
plaster, 1/16” lime
gauging plaster, 3/8”
7/16” gypsum sand
plaster, 1/16” lime
gauging plaster, 3/8”
Type X gypsum Type X gypsum
1090 162S None
1/4” gypsum, ½” Type
X gypsum
1/4” gypsum, ½” Typ
45-
½” Type X gypsum,
1/8” fiber cement 1/8” fiber cemen
veneer veneer
5/8” Type X gypsum 5/8” Type X gy
None
1240 250S 4 3” glass fiber
½” type X gypsum,
1/16” gypsum veneer
½” type X gypsum
1/16” gypsum vene
40-
None
S
Interior
(i
Walls and Interior Partitions
WP1015 250S 24 1-1/2” mineral fib 55-59
WP 2 ½” Type X gypsum (2) ½” Type X gypsum 54
WP1023 362S162 24 50-54
WP1041 362S162-33 24 None
” Type X gypsum, ½” Type X gypsum, ½:
50-54
WP 2 2” iber
½” Type
54
WP1051 250S 24 2” glass fiber

sum
50-54
WP1052 362S 24 e 50-54
WP1053 250S 24
pe
50-54
WP1070 250S 24 2” mineral fiber gypsum 45-49
WP1071 250S 24 2” mineral fiber 45-49
WP 2 3 ibe um 49
WP1073 250S 16 3-1/2” glass fibe ypsum 45-49
WP1076 250S 24 2-3/4&rdquo; glass fibe um 45-49
WP1081 362S 24 3” mineral fiber m 45-49
WP1082 362 3” mineral fiber psum 45-49
WP1085 250S 16 1” mineral fiber

45-49
WP 24
e
X gypsum
49
WP1121 362S162-33 24 None
½” Type X gypsum,
t 45-49
WP1200 362S162-18 24 None psum 40-44
WP1201 250S-33 16 5/8” Type X gypsum 5/8” Type X gypsum 40-44
WP 2
,
er
44
WP1290 250S 24
½” gypsum sand
pl ster, ½” gypsum lath
½” gypsum sand
plaster, ½” gypsum latha
40-44
WP1295 362S162-33 24 None 5/8” Type X gypsum
½” Type X gypsum,
¼” fiber cement board
40-44
WP1296 362S 16 3-1/2” mineral fiber 5/8” Type X gypsum
7/16” fiber cement
board
40-44
WP1340 162S 24 None 5/8” Type X gypsum 5/8” Type X gypsum 35-39
A-13

Residential Steel Framing – Fire and Acoustic Details

Table A6 – Gypsum Association Non-Load Bearing Walls – STC Rating (cont.)
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
tud
Spacing
n.)
Cavity Insulation Cover Exterior Cover
STC
Rating
(dB)
½” gypsum sand
plaster
½” gypsum sand
plaster
1400 162S None
5/8” gypsum sand
plaster over 3.4 lb.
Metal lath
5/8” gypsum sand
plaster over 3.4 lb.
Me
35-
(2) ½” Type X gypsum
Furring, (2) ½” Type
gypsum
r
½” type X gypsum,
5/8” Type X gypsum
½” type X gypsu
5/8” Type X gypsu
(2) 5/8”
5/8”& ½”Type X
gypsum
gypsu
½” cementitious, ¼”
ceramic tile
(2) ½” type X
½” Type X gypsum
gyps
s fiber (2) ½” Typ
P1522 362S 4 r
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
gypsum
55-
r (2) ½” Type X gypsum (2) ½” Type X gypsum
P1545
r (2) ½” Type X gypsum (2)
r
(2) 5/8” Type X (2)
gypsum
r
½” Type X gypsum, ½” T
3/32” gypsu
P1565 3 (2) ½” Type X gypsum
½” cementitious b
570 cf) ¾” Type X gypsum 3/
P1615 (2) ½” Type X gypsum (2) ½” Type X
625 pcf)
3/8” gypsum lath, ¾” 3/8” gypsum lath,
S
Interior
(i
Walls and Interior Partitions (cont.)
WP1370 250S 24 None 35-39
WP 15
tal lath
39
WP1470 350S162-33 24 3” mineral fiber
X
55-59
WP1505 250S 24 2-1/2” glass fibe
m,
m
55-59
WP1510 362S 24 2” glass fiber
Type X
gypsum, ¼” or 3/8”
m
55-59
WP1515 362S162-33 24 3” mineral fiber gypsum 55-59
WP1520 350S162-33 24 3” mineral fiber
Furring, (2) ½” Type X
um
55-59
WP1521 362S 24 3-1/2” glas e X gypsum (2) ½” Type X gypsum 55-59
W 2 3-1/2” glass fibe 59
WP1530 162S 24 1-1/2” glass fibe 50-54
W
WP1546
250S 24 1-1/2” glass fibe ½” Type X gypsum 50-54
WP1548 250S 24 2-1/2” glass fibe
5/8”Type X
gypsum
50-54
WP1560 250S 24 1-1/2” glass fibe
m veneer
ype X gypsum,
3/32” gypsum veneer
50-54
W 62S162-18 16 3” mineral fiber
½” Type X gypsum,
acker
50-54
WP1 350S 16 3” mineral fiber (2 p 4”Type X gypsum 50-54
W 250S 24 None gypsum 45-49
WP1 250S125-33 16 2” mineral fiber (3.4
gypsum sand plaster
¾”
gypsum sand plaster
45-49
W 250S 24 None (2) ½” Type X gypsum (2) ½” Type X gypsumP1630 45-49
WP1632 250S 24 None
” Type X gypsum,
½” glass matt gypsum
(2) ½” Type X gypsum
½
45-49
WP1711 362S 24 None
(2) 5/8” Type X
gypsum
(2) 5/8” Type X
gypsum
40-44
WP2800 152S 24 1-1/2” mineral fiber (3) &frac12;” Type X gypsum (3) ½” Type X gypsum 55-59FSTC
WP2921
WP2922
WP2924
162S 24 1-1/2” mineral fiber (3) ½” Type X gypsum (3) ½” Type X gypsum 50-54
A-14

Residential Steel Framing – Fire and Acoustic Details

Table A6 – Gypsum Association Non-Load Bearing Walls – STC Rating (cont.)
(Not complete construction details; consult original source for more information)
Source
Stud
Designation
Stud
Spacing
(in.)
Cavity Insulation Interior Cover Exterior Cover
STC
Rating
(dB)
WP2945 162S 1-1/2” mineral fiber ( m
gypsum
24 4) ½” Type X gypsu
(4) ½” Type X
60-64
WP2960
WP2961
WP2963
24 (4) ½” Type X gypsum162S 1-1/2” glass fiber
(4) ½” Type X
gypsum
55-59
(2) 3/4” Type X
gypsum
(2) ¾” Type X
gypsum
” Type X gy
) ½” Type X
gypsum
Chase W
each stud
8” Type X gypsu
ng, 5/8” T
gypsum cross braces
etween stud
cementiti
board, ¼” ceramic
tiles
FSTC
WP5015
Double
162S-33,
6.25” apart
1- for
,

16
1/2” mineral fiber
each stud
5/8” Type X gypsum
9.5” long, 5/8” Type X
gypsum cross braces
between studs
5/8” Type X gypsum 50-54
WP5070
Double
162S-33
1- for
”
24
1/2” mineral fiber
each stud
½” Type X gypsum, 6
long- ½” Type X
gypsum cross braces
between studs
½” Type X Gypsum,
½” cementitious
board, ¼” ceramic
tiles
60-64
FSTC
Double
gypsum, 6.25” long,
Type X gypsum cros
braces between stud
(2) 5/8” Type X
gypsum
apart
(2) 5/8” Type X
ypsum, 6.25” lon
Type X gypsum cross
(2) 5/8” Type X
gypsum
8” gypsum, ½” Ty
X gypsum
8” gypsum, ½” Type
gypsum
½” Type X gypsum,
Aluminum battens,
7/8” wide, w/ 25 gauge
steel track
½” Type X gypsum,
Aluminum battens,
7/8” wide, 25 gauge
steel track
250S 24
5/8” Type X gypsum,
Aluminum battens,
steel track
5/8” Type X gypsum,
Aluminum battens,
7/8” wide, 25 gauge
steel track
40-44
WP6135 250S 24 2” miner (2.63 pcf)
½” Type X gypsum,
r
studs
1/2” Ty ypsum,
over studs
al fiber Aluminum battens ove
pe X g
Aluminum battens 40-44
Walls and Interior Partitions (cont.)
WP2964 250S 24 2” mineral fiber (2pcf) 55-59
WP2970 162S 24 None (4) ½ psum
(4
50-54
alls
WP5005
Double
162S-33
16
1-1/2” mineral fiber for
5/ m,
6” lo ype X
b s
½” ous
60-64
WP5105 162S, 6.25”
apart
16 3-1/2” mineral fiber
(2) 5/8” Type X
s
s
55-59
WP5130
Double
162S, 6.25” 16 None
g g,
braces between studs
50-54
Movable and Office Partitions
WP5910 162S 24 2-3/4” fiber glass
3/ pe

3/
X
50-54
WP6010 2-3/4” fiber glass
WP6020 2” mineral fiber (3.7 pcf)
WP6025
250S 24
2” mineral fiber (3.8 pcf)

45-49
WP6040 3” glass fiber
WP6130 2” glass fiber
7/8” wide, w/ 25 gauge
WP6250 250S 24 None
5/8” Type X gypsum,
Aluminum battens over
studs
5/8” Type X gypsum,
Aluminum battens
over studs
35-39
A-15

Residential Steel Framing – Fire and Acoustic Details

Table A7 – Other Fire-Rated and STC Rated Assemblies
(Not com onstruction details; consult original source for more information) plete c
Stud Size
and Spacing
Bearing
Condition
Fir STC
Ratin
WP1200
RAL-TL93-70W
162-1
@ 24” o.c.
NLB
insulation gypsum
8” T
gypsum
362S 8 1-1/2” Cocoon 5/8” Type X 5/ ype X

50
250S Full cavity Cocoo 5/8” Type X 5/ ype X

50
WP1711
162-1
@ 24” o.c.
NLB
insulation
(2)
gy
8”
gypsum
362S 8

Full cavity Cocoon 5/8” Type X
psum
(2) 5/ Type X

58
U412
WP1548
250S162-1
@ 24” o.c.
NLB
Full ocoon
insulation
(2) 5/8” Type C
gypsum
(2) 5/8” Ty
gypsum
8
cavity C pe C
@ 16 insulation
(3) 5/8” Type C
gypsum
(3)
psum
3 h
600S 3-5/8” esilient channel,
ypsum board
5 oard
Nu-Wool
@ 16”
c. NLB
L
Resilient channel,
(2) 5/8” Type X
gypsum board
(2) 5
gyp

350S
o.
3-1/2”
WALLSEA
/8” Type X
sum board
- 60
Nu-Wool
350S @ 16”
.c. NLB (2
½” Type X
psum board
o
3-1/2”
WALLSEAL
Resilient channel,
) ½” Type X
gypsum board
(2)
gy
58
o
lient channel,
m board
350S
gypsum board
ohns Manville
362S @
o.c.
” ” fiberg
” gypsum board ½” g board 46
Johns Manville
362S @ 16”
o.c.
NLB
(U454)
3” mineral fiber
insulation (2 pcf)
lient channels,
ype C
gy sum board
(U435)
152S
3) ½” Type C
gypsum board
(3
gyp
” Type C
sum board
3 hr
(FSTC

Source

Cavity Insulation Interior Cover Exterior Cover
e-
Resistance g
(dB)
1 hr
RAL-TL98-7
162-18
@ 24” o.c.
NLB
n
insulation gypsum
8” T
gypsum
1 hr
2 hr
2 hr 58
U419
600S162-18
” o.c.
NLB
Full cavity Cocoon 5/8” Type C
gy
r 65
Nu-Wool
@ 16”
o.c.
NLB
WALLSEAL
R
5/8” g
/8” gypsum b - 54
-
Nu-Wool
350S @ 16”
.c. NLB
3-1/2”
WALLSEAL
Resi
(1) 5/8” Type X
gypsum board
(1) 5/8” Type X
gypsu
- 52
Nu-Wool
@ 16”
o.c.
NLB
3-1/2”
WALLSEAL
Resilient channel,
½”
½” gypsum board - 46
J
16

NLB
2 lass
(0.75 pcf)
½ ypsum -
2” rockwool
(2.0pcf)
½” gypsum board ½” gypsum board - 45
Hardirock

350S125-33 24
(2) ½” Type C
gypsum board
Resi
(2) ½” T
p
2 hr 55-59
Hardirock

125-18 16/24 1-1/2” glass fiber
( ) ½

50-54
)

A-17

Residential Steel Framing – Fire and Acoustic Details

Table A8 – STC/IIC Rated Floor Assemblies
ons nsult o r mor

(Not complete c truction details; co riginal source fo e information)
Source
Joist Size/
Designation
Stud
Spacing Ca
IIC
A
Figure
27
3 24 3-1/2” glass fiber
Carpet and pad, ¾” T&G plywood subwood
subflo annel, 5/8” gypsum

725S162-4 or on top, resilient ch
on bottom
(in.)
vity Insulation Specifications
STC/
Rating
(dB)
NAIM
56/71

A-18

Residential Steel Framing – Fire and Acoustic Details

Appen

List of Canadian Fire- and Sound-Rated Steel
m
dix B
Asse blies

Residential Steel Framing – Fire and Acoustic Details

Residential Steel Framing – Fire and Acoustic Details

B-1
The following is a comprehensive list of Canadian fire-ratings, STC ratings, and IIC ratings of
cold-formed steel wall and floor assemblies. All assemblies shown in this Appendix are not
complete construction details. Original source should be consulted for complete and detailed
information.

• 1 layer gypsum board
• Steel studs (0.46 mm, 0.018 in. thick)
• Insulation
• 2 layers gypsum board

Table B1 – Non-Load Bearing Walls – Fire-Rated Assemblies
Insulation Gypsum Board
Test
No.
Stud
Size
(mm)
Stud
Spacing
(mm)
Type
Thickness
(mm)
Type
Thickness
(mm)
Fire
Endurance
(min.)
F-07 31 x 92 610 None - Type X 12.7 65
F-09 31 x 92 610 Glass fiber 92 Type X 12.7 65
F-10 31 x 92 610
Mineral fiber
(58
92 Type X 12.7
4 mm wide)
ineral fiber
5 mm wide)
92
60
F-10B 31 x 92 610
M
(61
Type X 12.7 100
F-11 31 x 92 610 Cellulose 92 Type X 12.7 62
Notes:
Reference
Metric conversion: 1 in. = 25.4 mm

• 2 layers gypsum board
• Steel studs (0.46 mm, 0.018 in. thick)
• Insulation
• 2 layers gypsum board

Table B2 – Non-Load Bearing Walls – Fire-Rated Assemblies
report IRC-IR-675
Insulation Gypsum Board
Test
No.
Stud Size
(mm)
Stud
Spacing
(mm)
Type
Thickness
(mm)
Type
Thickness
(mm)
Fire
Endurance
(min.)
F-03 31 x 92 610 None - RL 12.7 63
F-05 31 x 92 610 None - RH 12.7 69
Notes:
Reference report IRC-IR-674
Metric conversion: 1 in. = 25.4 mm, 1 lb = 0.445 kg, 1 ft = 0.305 m
RL = low density gypsum board (7.35 kg/m
3
). RH = low density gypsum board (7.80 kg/m
3
)

Residential Steel Framing – Fire and Acoustic Details

B-2

• 1 layer gypsum board
• Steel studs (0.46 mm, 0.018 in. thick)
• Insulation
• 1 layer gypsum board

Table B3 – Non-Load Bearing Walls – STC Rating
Insulation Gypsum Board
Test
No.
Stud
Size
(mm)
Stud
Spacing
(mm)
Type
Thickness
(mm)
Type
Thickness
(mm)
STC
Rating
31 x 64 mm Non-load bearing Studs
057 31 x 64 406 None - Type X 15.9 35
032 31 x 64 610 None - Type X 15.9 35
058 31 x 64 406 Glass Fiber (G1) 64 Type X 15.9 39
064 31 x 64 406 Mineral Fiber (M1) 64 Type X 12.7 36
061 31 x 64 406 Mineral Fiber (M1) 64 Type X 15.9 38
069, 070 31 x 64 406 Mineral Fiber (M1) 64 Regular 12.7 33, 34
067 31 x 64 406 Mineral Fiber (M2) 64 Type X 12.7 35
059 31 x 64 406 Mineral Fiber (M2) 64 Type X 15.9 36
060 31 x 64 406 Mineral Fiber (M3) 57 Type X 15.9 36
068 31 x 64 406 Mineral Fiber (M3) 57 Regular 12.7 36
038 31 x 64 610 Glass Fiber (G1) 64 Type X 12.7 45
033, 073 31 x 64 610 Glass Fiber (G1) 64 Type X 15.9 44, 44
041, 043, 044 31 x 64 610 Glass Fiber (G1) 64 Regular 12.7 42, 43, 43
047 31 x 64 610 Mineral Fiber (M1) 64 Type X 12.7 43
034 31 x 64 610 Mineral Fiber (M1) 64 Type X 15.9 42
Notes:
Reference report IRC-IR-761

Residential Steel Framing – Fire and Acoustic Details

• 1 layer gypsum board
• Steel studs (0.46 mm, 0.018 in. thick)
• Insulation
• 1 layer gypsum board

Table B4 – Non-Load Bearing Walls – STC Rating
Insulation Gypsum Board
Test
o.
Size Spa
N
Stud
(mm) (mm)
Type
Stud
cing

Thickness
(mm)
Type
Thickness
(mm)
STC
Rating
31 x 92 mm Non-load bearing Studs
4 None - Type X 15.9 18 31 x 92 406 38
376 31 x 92 610 None - Type X 15.9 38
422, 425, 344 31 x 92 406 Glass Fiber (G1) 89 Type X 12.7 45, 45, 46
419, 443, 444,
074, 075, 325,
326, 352, 360,
026, 28, 02
92 Gl r (G1)
027, 0 9
31 x 406 ass Fibe 89 Type X 15.9
47, 45, 44,
47, 46, 49,
6
347, 3 5 31 x 406 Glass Fiber ( 89 Regular 2.7
0
31 x 406 Mineral Fiber (M 90 Type X 5.9
343 31 x 92 M2) 1406 Mineral Fiber ( 40 Type X 2.7 40
Mineral Fiber (M
49, 46, 46,
4
428, 61, 36 92 G1) 1
42, 41, 39,
4
445, 327, 328 92 1) 1 46, 47, 47
340 31 x 92 406 2) 40 Type X 15.9 41
002, 335, 336 31 x 92 406 Mineral Fiber (M2) 75 Type X 15.9 42, 45, 44
080 31 x 92 406 Mineral Fiber (M2) 90 Type X 12.7 40
001 31 x 92 406 Mineral Fiber (M2) 90 Type X 15.9 43
081 31 x 92 406 Mineral Fiber (M3) 90 Type X 12.7 39
3 Mineral Fiber (M3) 83 Type X 12.7 39 31 x 92 406 40
338, 003 31 x 92 406 Mineral Fiber (M3) 83 Type X 15.9 41, 39
4 406 Cellulose (C1) 40 Type X 15.9 39 31 x 92 45
0 Cellulose (C1) 90 Type X 15.9 49 31 x 92 406 45
438 31 x 92 406 Cellulose (C2) 90 Type X 15.9 44
413 31 x 92 6 Glass Fibe 90 R10 r (G1) egular 12.7 47
410 Glass Fiber (G1) Type X 31 x 92 610 90 12.7 48
10 90 15.9
0
396 2 6 Mineral (M2) T 131 x 9 10 Fiber 40 ype X 5.9 5
348, 367, 399, 324 31 x 92 6 Glass Fiber (G1) Type X
48, 49, 48,
5
4
026 31 x 92 610 Cellulose (C2) 90 Type X 12.7 48
31 x 152 mm Non-load bearing Studs
299 31 x 152 610 Glass Fiber (G1) 152 Type X 12.7 52
298 31 x 152 610 Glass Fiber (G1) 152 Type X 15.9 51
Notes:
Reference report IRC-IR-761

B-3

Residential Steel Framing – Fire and Acoustic Details

(0.46 mm, 0.018 in. thick)
• 2 layers gypsum board

• 1 layer gypsum board
• Steel studs
• Insulation
Table B5 – Non-Load Bearing Walls – STC Rating
Insulation Gypsum Board
est
o.
d
e
)
ud
acing
m)
ype
hickness
m)
Type
Thickness
(mm)
STC
Rating
31 x 64 mm Non-load bearing Studs
5 x 64 6 Fiber ( Type X 12.7 42
2 x 64 6 Fiber ( Type X 15.9 45
1 x 64 6 ineral Fiber (M1) 4 12.7 38
9 x 64 0 Glass Fiber (G1) 4 Type X 12.7 51
6 x 64 0 Glass Fiber (G1) 4 Type X 15.9 51
035 31 61 6
(
1 2.7 x 64 0 Glass Fiber (G1) 4
2) Type X
(1) Reg.
5.9/1 49
5 x 64 0 Glass Fiber (G1) 4 Regular 12.7 49
x 64 0 ineral Fiber (M1) 4 Type X 12.7 49
) Type X
R-761
conversion: . = 25.4 m
T
N
Stu
Siz
(mm
St
Sp
(m
T
T
(m
06 31 40 Mineral M1) 64
06 31 40 Mineral M1) 64
07 31 40 M 6 Regular
03 31 61 6
03 31 61 6
04 31 61 6
055 31 61 M 6
048 31 x 64 610 Mineral Fiber (M1) 64
(2
(1) Regular
12.7 48
Notes:
Reference report IRC-I
Metric 1 in m
B-4

Residential Steel Framing – Fire and Acoustic Details

• 1 layer gypsum board
• Steel studs (0.46 mm, 0.018 in. thick)
• Insulation
• 2 layers gypsum board
Table B6 – Non-Load Bearing Walls – STC Rating
Insulation Gypsum Board
est
o.
d
e
ud
acing
m)
ype
hickness
m)
Type
Thickness
(mm)
STC
Rating
31 x 92 mm Non-load bearing Studs
x 92 6 Fiber (G Type X 12.7
350 x 92 6 Fiber (G Type X 15.9
9, 348, 364,
366
x 92 6 lass Fiber (G1) 2 Regular 12.7
48, 47, 44,
46
329 31 40 M 9 x 92 6 ineral Fiber (M1) 2 Type X 15.9 53
341 31 x 92 406 Mineral Fiber (M2) 40 Type X 15.9 47
50
46
x 92 6 Cellulose (C1) 0 Type X 15.9 51
0 x 92 6 Cellulose (C1) 0 Type X 15.9
7 x 92 6 Cellulose (C2) 0 Type X 15.9 49
411 31 61 9 x 92 0 Glass Fiber (G1) 2 Type X 12.7 52
5 x 92 0 Glass Fiber (G1) 2 Regular 12.7 51
8 x 92 0 Glass Fiber (G1) 2 15.9 54
0 x 92 0 2
) Type X
5.9/1 55
397 31 61 M 4 x 92 0 ineral Fiber (M2) 0 Type X 15.9 51
7 x 92 0 ellulose (C1) 2 Type X 12.7 53
. = 25.4 m
T
N
Stu
Siz
(mm)
St
Sp
(m
T
T
(m
423, 426, 345 31 40 Glass 1) 92 51, 50, 51
420, 31 40 Glass 1) 92 52, 52
42
31 40 G 9
333 31 x 92 406 Mineral Fiber (M2) 75 Type X 15.9
337 31 x 92 406 Mineral Fiber (M3) 83 Type X 15.9
440 31 40 4
05 31 40 9 49
43 31 40 9
41 31 61 9
36 31 61 9 Type X
37 31 61 Glass Fiber (G1) 9
(2
(1) Regular
1 2.7
02 31 61 C 9
Notes:
Reference report IRC-IR-761
Metric conversion: 1 in m

B-5

Residential Steel Framing – Fire and Acoustic Details

• 2 layers gypsum board
.018 in. thick)
sum board

Table B7 – Non-Load Bearing Walls – STC Rating
• Steel studs (0.46 mm, 0
• Insulation
• 2 layers gyp
Insulation Gypsum Stud Board
Test
No.
Size
(mm) (mm)
e
Thickness
(mm)
ype
Thickness
(mm)
ring St
Mineral Fiber (M1) 64
063 31 x 64 406 Mineral Fiber (M1) 64 Type X 15.9 52
040 31 x 64 610 Glass Fiber (G1) 64 Type X 12.7 55
046 31 x 64 610 Glass Fiber (G1) 64 Regular 12.7 52
037 31 x 64 610 Glass Fiber (G1) 64 Type X 15.9 55
056 31 x 64 610 M Type X ineral Fiber (M1) 64 12.7 54
92 mm Non-load ing S
31 x 92 406 Glass Fiber (G1) 92 Type X 12.7
31 x 92 406 Glass Fiber (G1) 92 Type X 15.9
367
31 x 92 Glass Fiber (G1) 92 Regular 12.7
53
Stud
Spacing
Typ T
STC
Rating
31 x 64 mm Non-load bea uds
072 31 x 64 406 Regular 12.7 44
31 x bear tuds
424, 427, 346 55, 55, 52
421, 351 56, 56
430, 349, 363,
406
53, 49, 48,
441 31 x 92 406 Cellulose (C1) 40 Type X 15.9 53
331, 332 31 x 92 406 Mineral Fiber (M1) 92 Type X 15.9 55, 55
342 31 x 92 406 Mineral Fiber (M2) 40 Type X 15.9 52
077, 334 31 x 92 406 Mineral Fiber (M2) 75 Type X 15.9 52, 54
051 31 x 92 406 Cellulose (C1) 90 Type X 15.9 52
435, 436 31 x 92 406 Cellulose (C2) 92 Type X
(1) 12.7/
(3) 15.9
54, 54
412 31 x 92 610 Glass Fiber (G1) 92 Type X 12.7 55
416 31 x 92 610 Glass Fiber (G1) 92 Regular 12.7 53
369 31 x 92 610 Glass Fiber (G1) 92 Type X 15.9 58
398 31 x 92 610 Mineral Fiber (M2) 40 Type X 15.9 55
028 31 x 92 610 Cellulose (C2) 92 Type X 12.7 56
387 31 x 92 610 Cellulose (C2) 92 Type X 15.9 51
Notes:
Reference report IRC-IR-761
Metric conversion: 1 in. = 25.4 mm

B-6

Residential Steel Framing – Fire and Acoustic Details

• 2 layers gypsum board
• Steel studs (0.46 mm, 0.018 in. thick)
• Insulation
• 3 layers gypsum board

Table B8 – Non-Load Bearing Walls – STC Rating
Insulation Gypsum Board
Test
No.
Stud
Size
mm
Stud
Spacing
Mm
ype
hickness
mm)
Type
Thickness
(mm)
STC
Rating
31 x 92 mm Non-load bearing Studs
371 31 x 92 610
(3
(1) Regular
15 7 None -
) Type X
.7/12. 54
es:
eference report IR
conv
C-IR-761
• 1 rd
• G
• 1 gypsum rd
(Stud mm, 0. in. th
Table B9 – Non-Load Bearing Walls – STC Rating
Gypsum Board
Test
Size
(mm)
mm)
T
T
(
Not
R
Metric ersion: 1 in. = 25.4 mm

layer gypsum boa
• Steel studs and insulation
ap
• Steel studs and insulation
layer boa
s 0.46 018 ick)

No.
Stud Insulation Stud
Spacing
(mm)
Type
Thickness
(mm)
Type
Thickness
(
STC
Rating
31 x 40 mm Non-load bearing Studs
306 31 x 40 610 Mineral Fiber (M2) 40 Type X 12.7 53
309, 310 31 x 40 610 Mineral Fiber (M2) 40 Type X 15.9 54, 55
31 x 64 mm Non-load bearing Studs
303 31 x 64 610 Glass Fiber (G1) 64 Type X 12.7 54
300 31 x 64 610 Glass Fiber (G1) 64 Type X 15.9 55
Notes:
Reference report IRC-IR-761
Metric conversion: 1 in. = 25.4 mm

B-7

Residential Steel Framing – Fire and Acoustic Details

and insulation
• Steel Studs and insulation
• 2 layers gypsu
s 0.46 .018 ick)

• 1 layer gypsum board
• Steel studs
• Gap
m board
(Stud mm, 0 in. th
Table B10 – Non-Load Bearing Walls – STC Rating
Insulation
No.
Size
Type Type
mm)
Reference repo IRC-IR-7
etric conve : 1 in. = mm

ard
• G
• Stu d insula
• 2 s gypsum ard
(Studs mm, 0. in. th
T B11 on-Load Bear all C Ratin
Insulation Gypsum Board
No.
Stud
Size
Stud
Type Type
mm)
Gypsum Board
Test
Stud
(mm)
Stud
Spacing
(mm)
Thickness
(mm)
Thickness
(
STC
Rating
31 x 40 mm Non-load bearing Studs
307 31 x 40 610 Mineral Fiber (M2) 40 Type X 12.7 59
31 x 64 mm Non-load bearing Studs
304 31 x 64 610 Glass Fiber (G1) 64 Type X 12.7 60
301 31 x 64 610 Glass Fiber (G1) 64 Type X 15.9 61
Notes:
rt 61
M rsion 25.4

• 2 layers gypsum bo
• Steel studs and insulation
ap
d an tion
layer bo
0.46 018 ick)

able – N ing W s – ST g
Test
(mm)
Spacing
(mm)
Thickness
(mm)
Thickness
(
STC
Rating
31 x 40 mm Non-load bearing Studs
308 31 x 40 610 Mineral Fiber (M2) 40 Type X 12.7 63
320, 321 31 x 40 610 Mineral Fiber (M2) 40 Type X 15.9 65, 65
31 x 64 mm Non-load bearing Studs
305 31 x 64 610 Glass Fiber (G1) 64 Type X 12.7 62
302 31 x 64 610 Glass Fiber (G1) 64 Type X 15.9 64
Notes:
Reference report IRC-IR-761
Metric conversion: 1 in. = 25.4 mm

B-8

Residential Steel Framing – Fire and Acoustic Details

• 2 layers gypsum board
• Steel studs
• Insulation
• Resilient channels
• 2 layers gypsum board
Ta 12 – Load B alls – Fire-R

ble B earing W ating
Stu lation Gypsum Board
est
(mm)
Type
Thickness
(mm)
Fire d Insu
T
No.
Thickness
(mm)
Spacing
(mm)
R.C.
spacing
Type
Thickness
(mm)
Endurance
(min.)
41 x 92 mm Load bearing Studs
F37 0.91 406 406 None - Type X 12.7 77
F39 0.91 406 None None - Type X 12.7 83
F27 0.91 406 406 Glass Fiber 89 Type X 12.7 56
F35, F36 0.84 406 406 Glass Fiber 89 Type X 12.7 68, 63
F 406
Mineral
Fiber
38 0.91 406 90 Type X 12.7 59
90 Type X 12.7 74
se 90 Type X 12.7 71
F28 0.91 610 406
Mineral
Fiber
F 406 Cellulo31 0.91 406
Not
ests are from reference report IRC-IR-833
Metric conversion: 1 in. =

• 2 layers gypsum board
teel st
• Insulation
12.7 mm OSB Shear Panel (fire side)
• 1 layer gypsum board

Ta 13 – Wa Fire-R
es:
T
25.4 mm
• S uds
•
ble B Load Bearing lls – ating
Stud Insulation Gypsum Board
Test
Thickness Sp
No.
(mm) (mm)
acing
R.C.
spacing
(mm)
Type
Thickness
(mm)
Type
Thickness
(mm)
Fire
Endurance
(min.)
41 x 92 mm Load bearing Studs
F29 0.91 406 406 Glass Fiber 89 Type X 12.7 33
Notes:
Tests are from reference report IRC-IR-833.
Metric conversion: 1 in. = 25.4 mm
B-9


Residential Steel Framing – Fire and Acoustic Details

• 2 layers gypsum board
on
studs and insulation

Load Bearing Walls – Fire-Rating
• Steel studs and insulati
• Gap
• Steel
• 2 layers gypsum board
Table B14 –
Stud Insulation Gypsum Board
Test
No.
Thickness
(mm) m)
Type ype
(mm)
ring Studs
406 None -
406
Mineral
Fiber
90 Type X 84
IRC-I 3.
ic con : 1 in. = mm
Spacing
spacing
Thickness T
(m
R.C.
(mm)
(mm)
T
hickness
Fire
Endurance
(min.)
41 x 92 mm Load bea
F30,
F30R
0.91 406 Type X 12.7 100, 102
F26 0.91 406 12.7
Notes:
Tests are from reference report R-83
Metr version 25.4

• 1 layer gypsum board
• Steel studs
• Insulation
.)

le B15 – Load Bearing Walls – STC Rating

• Resilient channels (R.C
• 1 layer gypsum board
Tab
Stud Insulation Gypsum Board
Test
o.
Thickness Spacing
spac
(mm) (mm)
R.C.
N
ing
(mm)
Type
Thickness
(mm)
Type
Thickness
(mm)
STC
Rating
31 x 92 mm Load bearing Studs
TLA-105 0.91 406

(G1)
Type X406
Glass Fiber
89 12.7 45
Gl
(G1)
92 12.7
610
(G1)
Type X 15.9
49
610
Glass Fib
(G1)
Type X 15.9 50
10
(G1)
Glass Fiber
Type X 15.9 49
x 152 mm Load g St
TL-022
TLA-095
0.91 406 610
ass Fiber
Type X
48
47
TL-025
TLA-089
0.91 406
Glass Fiber
92
49

TL-354 1.22 406
er
92
TL-355 1.52 406 6

92
31 bearin uds
TL-353 1.22 406 610
Glass Fiber
(G1)
92 Type X 15.9 50
Notes:
“TL” tests are from reference report IRC-IR-761. “TLA” tests are from reference report IRC-IR-832.
Metric conversion: 1 in. = 25.4 mm
B-10

Residential Steel Framing – Fire and Acoustic Details

1

sum board
• Resilient channels (R.C.)
• 1 layer gypsum

B d Bearing W Rating

• 2 layers gyp
• Steel studs
• Insulation
board
Table 16 – Loa alls– STC
Insulation Gypsum BoardR.C.
spacing
Type
Thickne
31 x 92 mm earing Studs Load b
019 0.91 406 610
Glass Fiber
(G1)
2 .7 9 Type X 12 54
016 1.52 406 610
r
2 .7
Glass Fibe
(G1)
9 Type X 12 53
023 0.91 406 610
Mineral

2 .7
Fiber (M1)
9 Type X 12 54
013 1.52 406 610
l
1)
2 .7
Minera
Fiber (M
9 Type X 12 53
ferenc rt IRC-IR 1
Stud
Test
No.
Thickness
(mm)
Spacing
(mm)
(mm)
ss
(mm)
Type
Thickness
(mm)
STC
Rating

Notes:
Re e repo -76
Metric conversion: 1 in. = 25.4 mm

• 1 layer gypsum board
• Steel studs
• Insulation
.)
sum board

aring Walls– STC Rating

• Resilient channels (R.C
• 2 layers gyp
Table B17 – Load Be
Stud Insulation Gypsum Board
Test
No.
Thickness
(mm)
Spacing
(mm)
(mm)
(mm)
R.C.
spacing
Type
Thickness
Type
Thickness
(mm)
STC
Rating
31 x 92 mm Loa tuds d bearing S
021 0.91 406 610
Glass Fiber

X
(G1)
92 Type 12.7 54
610
Glass Fiber
92
tes:
018 1.52 406
(G1)
Type X 12.7 53
No
Reference report IRC-IR-761
onversion: 1 in. = 25.4 mm Metric c

B-1

Residential Steel Framing – Fire and Acoustic Details

ation
Table B1 oad Bear – STC Ra
• 2 layers gypsum board
• Steel studs
• Insul
• Resilient channels (R.C.)
• 2 layers gypsum board

8 – L ing Walls ting
Stud Insulation Gypsum Board
Test
Spacing
R.C.
spacing
(mm)
Type
Thickness
(mm)
Thick
STC
Glass Fiber
No.
Thickness
(mm)

(mm)
Type
ness
(mm)

Rating
31 x 92 mm Load bearing Studs
TLA-065 0.91 406 406 89 Type X 12.7 57
TLA-079 1.52 406 406 Glass Fiber 89 Type X 12.7 57
TLA-081 1.52 406 406
Mineral
Fiber
90 Type X 12.7 56
TLA-071 0.91 406 406 Glass Fiber 89 Type X 15.9 58
TL 8 406 Glass Fiber 89 Type X 15.9 A-0 1 1.52 406 57
TLA-063 0.91 406 610 None - Type X 12.7 50
TL 0
TLA-099
610
Glass Fiber
(G1)
90 Type X 12.7
-02
0.91 406
60
59
TL-017 1.52 406 610
Glass Fiber
(G1)
90 Type X 12.7 59
TL-024 0.91 406
Fiber (
0 T610
M1)
9 ype X 12.7
L-014 1.52 406 610
ber (M1)
90 ype X 12.7 59
610 None -
TLA-093
0.91 406 Glass Fiber 89 Type X 15.9
59
otes:
“TL” tests a om ref repo IR-76
TLA” test
Metric conv .4 mm
Mineral
60
T
Mineral
Fi
T
TLA-075 0.91 406 Type X 15.9 51
TLA-073
610
59
N
re fr erence rt IRC- 1.
“ s are from reference report IRC-IR-832.
ersion: 1 in. = 25

B-12

Residential Steel Framing – Fire and Acoustic Details

• 1 layer gypsum board
• 65 mm non-load bearing steel studs and
sum board
tuds and
• 1 layer gypsum board

Table B19 d Bearin STC Rati
insulation
• Gap
• 1 layer gyp
• 92 mm load bearing steel s
insulation
– Loa g Walls– ng
Insulation Gypsum Board
Test
R.C.
pacing
(mm)
Type
(mm)
STC
1 x 9 Load beari
Glass Fiber
A” t from r e rep -IR-8
Stud
No.
Thickness
(mm)
Spacing
(mm)
s
Thickness

Type
Thickness
(mm)
Rating
3 2 mm ng Studs
TLA-077 0.46, 0.91 406 - 89 Type X 15.9 48
Notes:
“TL ests are eferenc ort IRC 32.
Metric conversion: 1 in. = 25.4 mm

• 1 layer sub-floor sheathing
• Steel floor joists
• Insulation
• Resilient channels at 406 mm o.c.
X gypsum board

ble B20 – Floors – Fire-Rating

• 1 layer 12.7 mm Type
Ta
Joist Sub-floor Insulation
Test
No.
Thickness
(mm)
Depth
(mm) (mm)
Type
(mm)
Type
Spacing Thickness Thickness
(mm)
Fire
Endurance
(min.)
FF-25 1.22 203 Plywood 15.9
Roc
fiber
406
k
90 46
tes: No
Reference report IRC-IR-764
Metric conversion: 1 in. = 25.4 mm

B-13

Residential Steel Framing – Fire and Acoustic Details

floor sheathing
joists
• Resilient channels at 406 mm o.c.
• 2 layers 12.7 mm Type X gypsum board

Table B21 – Floors – Fire-Rating
• 1 layer sub-
• Steel floor
• Insulation
Joist Sub-floor Insulation
Test
Depth
(mm)
Type
ness
(mm)
ness
Fire
lass
lass
Notes:
Reference report IRC-IR-764
ersio . = 25.4 mm

mm crete
• 1 layer sub-floor sheathing
teel f joists
sula
• Resilient channels at 406 mm o.c.
laye 7 mm e X gy bo
Table B22 – Floors – Fire-Rating
Metric conv n: 1 in

• 38 con
• S loor
• In tion
• 2 rs 12. Typ psum ard

oist Sub-floor Insulat
t
re
No.
Thickness
(mm)

(mm)
Spacing Thick
Type
Thick
(mm)
Endurance
(min.)
FF-22 1.22 203 406 Plywood 15.9 None - 74
FF-23 1.22 203 406 Plywood 15.9
G
fiber
90 68
FF-24 1.22 203 610 Plywood 15.9
G
fiber
90 69
J ion
Tes
No.
(mm) (mm) (mm)
Thickness Depth Spacing
Type
Thickness
(mm)
Type
Thickness
(mm)
Fi
Endurance
(min.)
FF-27 1.22 203 406 Plywood 15.9
Glass
fiber
90 60
Notes:
Reference report IRC-IR-764
Metric conversion: 1 in. = 25.4 mm

B-14

Residential Steel Framing – Fire and Acoustic Details

• 1 layer OSB
• Steel floor joists
Insulation •
ient channels at 610 mm o.c.
X gypsum board

Table B23 – Floors – STC Rating
• Resil
• 1 layer 15.9 mm Type
Joist
Tes
Sub-floor Insulation
t
No.
Thickness
(mm)
Depth
(mm) (mm)
Type
(mm)
Type
(m
Spacing Thickness Thickness
m)
IIC
Rating
STC
Rating
TLF-057/028 1.91 203 OSB ass fiber406 15.1 Gl 152 45
1.52 203 406 Glass fi 45 51
2 1.2 203 406 1 Glass fi 15 44 50
1.52 203 Glass 44
406 OSB 15.1 Glas
LF-069/03 1.52 SB 15.1 152 44 52
LF-067/03 1.52 SB 15.1 152 44 53
52
TLF-059/029 OSB 15.1 ber 152
TLF-061/030 OSB 5.1 ber 2
TLF-063/031 610 OSB 15.1 fiber 152 53
TLF-065/032 1.52 254 s fiber 152 44 51
T 4 305 406 O Glass fiber
T 3 203 610 O Glass fiber
TLF-009/004 1.52 203 406 OSB 15.1 None - 35 44
T 15.1 Glass fiber 152 LF-001a/001 1.52 203 406 OSB 43 50
TLF-005/002 1.52 203 406 OSB 15.1
Mineral
fiber
140 45 51
TLF-011/005 1.52 203 406 OSB 15.1 Cellulose 90 44 51
TLF-011/005 1.52 203 406 OSB 15.1 Cellulose 140 45 52
N
R
otes:
eference report IRC-IR-766
Met c

• 1 layer OSB
• Steel floor joists
• Insulation
Resilient channels at 610 mm o.c.
1 lay g oa

Table B24 – Floors – STC and IIC Ra
ric onversion: 1 in. = 25.4 mm
• 25 mm gypsum concrete
•
• er 15.9 mm Type X ypsum b rd
ting
Joist Sub-floor Insulation
Test
No.
Thickness Depth
(mm) (mm)
Spacing
(mm)
Type
Thickness
(mm)
Type
Thickness
(mm)
IIC
Rating
STC
Rating
TLF-
079/039
1.52 203 406 OSB 15.1 None - 24 55
TLF-
081/040
1.52 203 406 OSB 15.1
Glass
fiber
152 28 60
Notes:
Reference report IRC-IR-766
Metric conversion: 1 in. = 25.4 mm
B-15

Residential Steel Framing – Fire and Acoustic Details

B-16

Residential Steel Framing – Fire and Acoustic Details

PP D C
ET C N S N F TORS

A EN IX
M RI CO VER IO AC

Residential Steel Framing – Fire and Acoustic Details

The following list provides the conversion relationship between U.S. customary units and the
International System (SI) units. A complete guide to the SI system and its use can be found in
ASTM E 380, Metric Practice.

To convert from To Multiply by To convert from To Multiply by
Length Stress or pressure
Inch (in.) Micrometer (µm) 25,400 Kilogram/square meter (kg/sq. m) 4.8824Pound/sq. foot (psf)
PInch (in.) Millimeter (mm) 25.4 ound/sq. foot (psf) Pascal (Pa) 47.88
Inch (in.) Centimeter (cm) 2.54 eight) Mass (w
Pound (lb.)
Ton, 2000 lb
Inch (in.) Meter (m) 0.0254 Kilogram (kg) 0.4535924
Foot (ft) Meter (m) 0.3048 Kilogram (kg) 907.1848
Yard (yd) Meter (m) 0.9144 Kilogram (kg) 0.0000648Grain
Mile (mi) Kilometer (km) 1.6
eight) per length) Mass (w
Kip per linear foot
Area

Kilogram per meter (kg/m) 0.001488
(klf)
Pound per linear foot
(plf)
Square foot (sq. ft) Square meter (sq. m ) 0.0929

Kilogram per meter (kg/m) 1.488
Square inch (sq. in) Square centimeter (sq. cm) 6.452 Moment
1 foot-pound (ft-lb.)Square inch (sq. in.) Square meter (sq. m) 0.00064516 Newton-meter (N-m) 1.356
Square yard (sq. yd) Square meter (sq. m) 0.8391
) Mass per volume (density
Square mile (sq. mi) Square kilometer (sq. km) 2.6 ound per cubic foot

Kilogram per cubic meter
(kg/cu m)
16.01846P
(pcf)
Volume
yard Kilogram per cubic meter
(kg/cu m)
0.5933Pound per cubic
(lb/cu yd)
Cubic inch (cu in.) Cubic centimeter (cu cm) 16.387064 Velocity
bic meter (cu m) 0.00001639 Mile per hour (mph) Kilometer per hour

Cubic inch (cu in.) Cu (km/hr) 1.60934
Cubic foot (cu ft) Cubic meter (cu m) 0.02831685 Mile per hour (mph) Kilometer per second (km/sec) 0.44704
Cubic yard (cu yd) Cubic meter (cu m) 0.7645549 Temperature
Gallon (gal) Can.
liquid
Liter 4.546 Degree Fahrenheit
(°F)
Degree Celsius (°C) tC = (tF - 32)/1.8

Gallon (gal) Can.
liquid
Cubic meter (cu m) 0.004546 Degree Fahrenheit
(°F)
Degree Kelvin (°K) tK= (tF+59.7)/1.8
Gallon (gal) U.S.
liquid*
Liter 3.7854118 Degree Kelvin (°K) Degree Celsius (°C) t
C
= (t
K
-273.15)
Gallon (gal) U.S.
liquid
Cubic meter (cu m) 0.00378541 Degree Celsius (°C) Degree Fahrenheit (°F) t
F
= 1.8t
C
+ 32
Fluid ounce (fl oz) Milliliters (ml) 29.57353 * One U.S. gallon equals 0.8327 Canadian gallon
Fluid ounce (fl oz) Cubic meter (cu m) 0.00002957 ** A Pascal equals 1000 Newton per square meter.
Force
Kip (1000 lb.) Kilogram (kg) 453.6
The prefixes and symbols below are commonly used to form names and
symbols of the decimal multiples and submultiples of the SI units
Kip (1000 lb.) Newton (N) 4,448.222 Multiplication Factor Prefix Symbol
Pound (lb.) Kilogram (kg) 0.4535924 1,000,000,000 = 10
9
Giga G
Pound (lb.) Newton (N) 4.448222 1,000,000 = 10
6
Mega M
Stress or pressure
1,000 = 10
3
Kilo k
Kip/sq. inch (ksi) Mega Pascal (Mpa) 6.894757 0.01 = 10
-2
Centi c
Kip/sq. inch (ksi) Kilogram/square centimeter
(kg/sq. cm)
70.31 0.001 = 10
-3
Milli m
Pound/sq. inch (psi) Kilogram/square centimeter
(kg/sq. cm)
0.07031 0.000001 = 10
-6
Micro µ
Pound/sq. inch (psi) Pascal (Pa) ** 6,894.757 0.000000001 = 10
-9
Nano n
Pound/sq. inch (psi) Mega Pascal (Mpa) 0