Rim Board Fire Assembly Applications

TER No. 1005-01  |  Issue Date: May 28, 2010

TECO Certified Rim Board in Fire-Rated Assemblies

Division 06 – Wood and Plastics
Section 06170 – Prefabricated Structural Wood

1. Product Lines Evaluated

1.1. TECO Certified Rim Board is available in two grades:

  • 1.1.1. Standard: 1" Rim Board (25 mm)
  • 1.1.2. Performance: 1⅛" Rim Board (29 mm)

1.2. TECO Certified Rim Board is qualified to the TECO Rim Board Product Standard (RB 133) and must be composed of wood. It may be in the form of oriented strand board1 or other composite structural panels. Oriented strand lumber or laminated veneer lumber manufactured in accordance with ASTM D5456-06 is also acceptable.

2. Performance Evaluation

2.1. The International Building Code (IBC)2 and the National Building Code of Canada (NBC)3 allow for the component additive method (CAM) for calculating fire resistance ratings of protected wood-frame walls, floors, and roofs.

2.2. Code References:

Code Applicable Chapters/Sections
IBC 2009 Chapter 7, Section 703.3, and Section 721
IBC 2006 Chapter 7, Section 703.3, and Section 721
NBC 2005 Appendix D

3. Applications

TECO Certified Rim Board is used to tie floor joists together in order to carry the lateral and vertical loads from the walls past the I-joist, truss, etc. system to the sill plate and foundation wall.

4. Fire-Resistant Rim Board Assembly Applications

The rim board assemblies in Figures 1–7 will achieve fire-resistance ratings of one hour. The assemblies listed are based on the char rates of TECO Certified Rim Board at the minimum specifications.

1 Per RB 133, the base OSB panel must be qualified to US Dept. of Commerce Voluntary Product Standard PS2 or CSA O325.

2 2009 IBC Section 703.3 Alternative methods for determining fire resistance allows for calculations in accordance with Section 721.

3 Appendix D of the NBC details the "component additive method" to establish fire ratings of an assembly.

Assembly No. 1

Figure 1: TECO Certified Rim Board One-Hour Assembly No. 1 (Shown as I-Joist Perpendicular to Rim Board)

Note: Upper Load Uniformly Distributed to Both Walls and Load is Transferred to Non-Fire-Exposed Wall When Rim Board Support on Fire-Exposed Wall is Lost to Fire.

  1. Continuous TECO Certified Rim Board 1" or TECO Certified Rim Board 1⅛"
  2. Continuous ½" Type X gypsum board fastened to rim board with 1½" Type W screws 12" on center
  3. One-hour-rated wall construction
  4. Floor or roof/ceiling assembly for story above
  5. Un-rated floor/ceiling assembly
  6. ½" min. gypsum board ceiling, taped and filled
  7. I-Joists are shown in this graphic but the structural element may be any structural element assembly applied as specified, with or without a fire-endurance-rated assembly

Component Additive Calculation for Assembly No. 1

Component 1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board
Time (min.)
½" Gypsum 15 15
Rim Board 33.75 39.65
½" Type X Gypsum 25 25
73.75 79.65

Assembly No. 2

One-Hour Assembly No. 2 (Shown as I-Joist Perpendicular to Rim Board)

Note: Upper Load Uniformly Distributed to Both Walls and Load is Transferred to Non-Fire-Exposed Wall When Rim Board Support on Fire-Exposed Wall is Lost to Fire.

  1. Continuous TECO Certified Rim Board 1" or TECO Certified Rim Board 1⅛"
  2. Continuous ½" Type X gypsum board fastened to rim board with 1½" Type W screws 12" on center
  3. 45-minute or one-hour-rated wall construction
  4. Floor or roof/ceiling assembly for story above
  5. Un-rated floor/ceiling assembly
  6. I-Joists are shown in this graphic but the structural element may be any structural element assembly applied as specified, with or without a fire-endurance-rated assembly

Component Additive Calculation for Assembly No. 2

Component 1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board
Time (min.)
Rim Board 33.75 39.65
½" Gypsum 15 15
½" Gypsum 15 15
63.75 69.65

Assembly No. 3

One-Hour Assembly No. 3 (Shown as I-Joist Perpendicular to Rim Board

Note: Upper Load Applied Individually to Each Wall – Load is Not Transferred to Non-Fire-Exposed Wall When Rim Board Support on Fire-Exposed Wall is Lost to Fire.

  1. Continuous TECO Certified Rim Board 1" or TECO Certified Rim Board 1⅛"
  2. Continuous ⅝" Type X gypsum board fastened to rim board with 1½" Type W screws 12" on center
  3. 45-minute or one-hour-rated wall construction
  4. Floor or roof/ceiling assembly for story above
  5. Un-rated floor/ceiling assembly
  6. I-Joists are shown in this graphic but the structural element may be any structural element assembly applied as specified, with or without a fire-endurance-rated assembly

Component Additive Calculation for Assembly No. 3

Component 1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board
Time (min.)
Rim Board 33.75 39.65
⅝" Type X Gypsum 40 40
73.75 79.65

Assembly No. 4

One-Hour Assembly No. 4 (Shown as I-Joist Perpendicular to Rim Board)

Note: Upper Load Applied Individually to Each Wall – Load is Not Transferred to Non-Fire-Exposed Wall When Rim Board Support on Fire-Exposed Wall is Lost to Fire.

  1. Continuous TECO Certified Rim Board 1" or TECO Certified Rim Board 1⅛"
  2. Continuous ½" gypsum board fastened to rim board with 1½" Type W screws 12" on center (optional)
  3. 45-minute or one-hour-rated wall construction
  4. Floor or roof/ceiling assembly for story above
  5. 45-minute-rated floor/ceiling assembly
  6. I-Joists are shown in this graphic but the structural element may be any structural element assembly applied as specified, with or without a fire-endurance-rated assembly

Component Additive Calculation for Assembly No. 4

Component Without Optional Gypsum With Optional ½" Gypsum
1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board 1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board
Time (min.)
45 min. Rated Floor/Ceiling Assembly4 45 45 45 45
½" Gypsum (optional) 15 15
Rim Board 33.75 39.65 33.75 39.65
78.75 84.65 93.75 99.65

4 Since the walls are rated for 60 min. and the floor/ceiling assembly is rated for 45 min., the TECO Certified Rim Board only needs to provide at least 15 min. additional fire resistance.

Assembly No. 5

One-Hour Assembly No. 5 (Shown as I-Joist Perpendicular to Rim Board)

Note: Upper Load Applied Individually to Each Wall – Load is Not Transferred to Non-Fire-Exposed Wall When Rim Board Support on Fire-Exposed Wall is Lost to Fire.

  1. Continuous TECO Certified Rim Board 1" or TECO Certified Rim Board 1⅛"
  2. 45-minute or one-hour-rated wall construction
  3. Floor or roof/ceiling assembly for story above
  4. One-hour-rated floor/ceiling assembly
  5. I-Joists are shown in this graphic but the structural element may be any structural element assembly applied as specified, with or without a fire-endurance-rated assembly

Component Additive Calculation for Assembly No. 5

Component 1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board
Time (min.)
One-Hour-Rated Floor/Ceiling Assembly5 60 60
Rim Board 33.75 39.65
93.75 99.65

5 Since the walls are rated for 60 min. and the floor/ceiling assembly is rated for 60 min., the TECO Certified Rim Board does not need to provide any additional fire resistance to achieve a one-hour rating.

Assembly No. 6

One-Hour Assembly No. 6 (Shown as I-Joist Perpendicular to Rim Board)

Note: Single One-Hour-Rated Partition Wall

  1. Continuous TECO Certified Rim Board 1" or TECO Certified Rim Board 1⅛"
  2. One-hour-rated 2x6 wall construction
  3. Floor or roof/ceiling assembly for story above
  4. One-hour-rated floor/ceiling assembly
  5. I-Joists are shown in this graphic but the structural element may be any structural element assembly applied as specified, with or without a fire-endurance-rated assembly

Component Additive Calculation for Assembly No. 6

Component 1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board
Time (min.)
One-Hour-Rated Floor/Ceiling Assembly6 60 60
Rim Board 33.75 39.65
93.75 99.65

6 Since the walls are rated for 60 min. and the floor/ceiling assembly is rated for 60 min., the TECO Certified Rim Board does not need to provide any additional fire resistance to achieve a one-hour rating.

Assembly No. 7

One-Hour Assembly No. 7 (Shown as I-Joist Perpendicular to Rim Board)

Note: Single One-Hour-Rated Partition Wall

  1. Continuous TECO Certified Rim Board 1" or TECO Certified Rim Board 1⅛"
  2. One-hour-rated 2x6 bearing wall or 2x4 staggered on 2x6 plates
  3. 45-minute or one-hour-rated floor/ceiling assembly
  4. I-Joists are shown in this graphic but the structural element may be any structural element assembly applied as specified, with or without a fire-endurance-rated assembly

Component Additive Calculation for Assembly No. 7

Component 45 min. Rated Floor/Ceiling Assembly7 One Hour Rated Floor/Ceiling Assembly8
1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board 1" TECO Certified Rim Board 1⅛" TECO Certified Rim Board
Time (min.)
Rated Floor/Ceiling Assembly 45 45 60 60
Rim Board 33.75 39.65 33.75 39.65
78.75 84.65 93.75 99.65

7 Since the wall is rated for 60 min. and the floor/ceiling assembly is rated for 45 min., the TECO Certified Rim Board needs to provide an additional fire resistance of 15 min. to achieve a one-hour rating.

8 Since the wall is rated for 60 min. and the floor/ceiling assembly is rated for 60 min., the TECO Certified Rim Board does not need to provide any additional fire resistance to achieve a one-hour rating.

5. Installation

TECO Certified Rim Board shall be installed in accordance with the Rim Board Design and Installation Guide – Canada9 or Rim Board Design and Installation Guide – United States10.

6. Conditions of Use

The manufactured rim board must be TECO Certified Rim Board and comply with all of the requirements of RB 133.

7. Test and Engineering Substantiating Data

Based on Calculated Fire Resistance Rating of TECO Certified Rim Board Assemblies by Qualtim, Inc. dated May 28, 2010.

8. Identification

TECO Certified Rim Board must be identified with the following information:

  • 8.1.1. Name of the manufacturer or the TECO mill number
  • 8.1.2. TECO's registered Certification Mark
  • 8.1.3. Grade of the rim board
  • 8.1.4. Thickness
  • 8.1.5. RB 133 standard

Figure 8: Example Grade Stamps for TECO Certified Rim Board per RB 133

9. Report Date

This Testing and Evaluation Report shall be re-evaluated one year from the issue date.

10. Findings

The Structural Building Components Research Institute (SBCRI) is an ACLASS11 accredited state-of-the-art testing and research facility. It is one of the few facilities that has the capability of testing structural assemblies as they are actually built and installed in the field and is an approved agency as defined in Section 17 of the IBC. Through SBCRI's engineering partner Qualtim, Inc.12, calculations have been prepared by licensed engineers for the fire endurance performance of TECO Certified Rim Board. Qualtim/SBCRI has listed and can provide detailed and sufficient technical data to substantiate the proposed use of TECO Certified Rim Board in the assemblies and applications defined above. This Testing and Evaluation Report finds that:

Data and engineering analysis review has found that the TECO Certified Rim Board Fire-Rated Assemblies as described in this Testing and Evaluation Report conform with or are suitable alternates to that specified in the code references listed in Section 2.

Responsibility Statement

The information contained herein is based on a product evaluation performed in accordance with the referenced testing and/or analysis using generally accepted engineering practices. Product quality control is the responsibility of the manufacturer. Consult your local jurisdiction or design professional to assure compliance with the local building code and the proper detailing and application for the intended purpose. Qualtim, Inc. (www.qualtim.com) and SBC Research Institute (www.sbcri.info) do not make any warranty, express or implied, or assume any legal liability or responsibility for the use, application of, and/or reference to opinions, findings, conclusions, or recommendations included in this Testing and Evaluation Report.