AISI STANDARD. Supplement 3 to the Standard for Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition

Transcription

1 AISI S230 07/S3-12 AISI STANDARD Supplement 3 to the Standard for Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition 2012 Endorsed by Steel Framing Alliance

2 ii AISI S230-07/S3-12 DISCLAIMER The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Commentary. With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material will become dated. It is anticipated that AISI will publish updates of this material as new information becomes available, but this cannot be guaranteed. The materials set forth herein are for general purposes only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a design professional. Indeed, in many jurisdictions, such review is required by law. Anyone making use of the information set forth herein does so at their own risk and assumes any and all liability arising therefrom. 1 st Printing 2012 Copyright American Iron and Steel Institute 2012

3 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition iii PREFACE The American Iron and Steel Institute Committee on Framing Standards has developed this Supplement 3 to AISI S230-07, the Standard for Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition, to allow the 2007 Edition of AISI S230 to be used in conjunction with the 2010 Edition of ASCE 7. Supplement 3 to AISI S updates the referenced documents. Supplement 3 also eliminates 97-mil clip angle bearing stiffeners from Tables B2-1 through B2-4, for consistency with the design provisions in AISI S210-07, the North American Standard for Cold-Formed Steel Framing - Floor and Roof System Design, 2007 Edition. Supplement 3 to AISI S does not replace Supplement 2 to AISI S230-07, but is intended to be used in conjunction with AISI S with Supplement 2. Supplement 3 also includes Errata issued on July 29, 2009, September 10, 2010, and May 19, When packaged together, this complete set of documents is designated as AISI S w/s3-12. The Committee acknowledges and is grateful for the contributions of the numerous engineers, researchers, producers and others who have contributed to the body of knowledge on the subjects. The Committee wishes to also express their appreciation for the support of the Steel Framing Alliance.

4 iv AISI S230-07/S3-12 AISI COMMITTEE ON FRAMING STANDARDS Richard Haws, Chairman Nucor Corporation Steve Fox, Vice Chairman Canadian Sheet Steel Building Institute Helen Chen, Secretary American Iron and Steel Institute Don Allen DSi-Engineering, LLC Bill Babich ITW Building Components Group Jeff Brink National Council of Structural Engineers Associations John Butts John F. Butts & Associates Brad Cameron Cameron & Associates Engineering Randy Daudet Nader Elhajj Pat Ford Curt Kinney Jeff Klaiman Roger LaBoube Rob Madsen John Matsen Cris Moen James Moses Kenneth Pagano Mike Pellock Nabil Rahman Greg Ralph Benjamin Schafer Fernando Sesma Sutton Stephens Tom Trestain Steven Walker Robert Wessel Simpson-Strong Tie FrameCAD Solutions Steel Framing Industry Association Super Stud Building Products ADTEK Engineers Wei-Wen Yu Center for Cold-Formed Steel Structures Supreme Steel Framing System Association Matsen Ford Design Associates Virginia Tech LiteSteel Technologies America Scosta Corporation Aegis Metal Framing The Steel Network ClarkDietrich Building Systems Johns Hopkins University California Expanded Metal Products Pacific Northwest Engineering T.W.J. Trestain Structural Engineering Steven H. Walker, P.Eng. Gypsum Association Lei Xu University of Waterloo Cheng Yu University of North Texas Rahim Zadeh Steel Stud Manufacturers Association

5 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition v PRESCRIPTIVE METHOD SUBCOMMITTEE Sutton Stephens, Chairman Pacific Northwest Engineering Helen Chen, Secretary Don Allen Randy Daudet Jim DesLaurier Nader Elhajj Steven Fox Perry Green Richard Haws Curt Kinney Stephen Linch John Matsen James Moses Greg Ralph Fernando Sesma Lei Xu Rahim Zadeh American Iron and Steel Institute DSi-Engineering, LLC Simpson Strong-Tie Marino/Ware FrameCAD Solutions Canadian Sheet Steel Building Institute Consultant Nucor Corporation Super Stud Building Products Telling Industries Matsen Ford Design Associates LiteSteel Technologies America ClarkDietrich Building Systems California Expanded Metal Products University of Waterloo Steel Stud Manufacturers Association

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7 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition vii TABLE OF CONTENTS SUPPLEMENT 3 TO THE STANDARD FOR COLD-FORMED STEEL FRAMING PRESCRIPTIVE METHOD FOR ONE AND TWO FAMILY DWELLINGS, 2007 EDITION DISCLAIMER...ii PREFACE...iii AISI COMMITTEE ON FRAMING STANDARDS... iv PRESCRIPTIVE METHOD SUBCOMMITTEE... v CHANGES TO CHAPTER A. GENERAL...1 A1 Scope... 1 A1.1 Limits of Applicability... 1 A2 Definitions... 2 A3 Referenced Documents... 2 A4 Limitations of Framing Members... 3 A4.1 General CHANGES TO CHAPTER B. CONNECTIONS...4 CHANGES TO CHAPTER E. WALL FRAMING...7 E7.3 L-Header CHANGES TO CHAPTER F. ROOF FRAMING F3 Roof Rafters F3.4 Roof Rafter to Ceiling Joist and Ridge Member Connection F4.4 Hip Framing Connections F6 Roof Trusses... 21

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9 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition 1 SUPPLEMENT 3 TO THE STANDARD FOR COLD-FORMED STEEL FRAMING PRESCRIPTIVE METHOD FOR ONE AND TWO FAMILY DWELLINGS 2007 EDITION CHANGES TO CHAPTER A. GENERAL A1 Scope [Note: Add a fourth paragraph and a User Note in Section A1, as shown below.] The provisions in this standard shall apply to the construction of detached one- and twofamily dwellings, townhouses, and other attached single-family dwellings not more than three stories in height using repetitive in-line framing practices. Buildings complying with the limitations herein shall be constructed in accordance with this standard and AISI S200. Alternatively, such dwellings shall be permitted to be designed by a design professional. This standard shall not preclude the use of other materials, assemblies, structures or designs not meeting the criteria herein, when the other materials, assemblies, structures or designs demonstrate equivalent performance for the intended use to those specified in this standard. Where there is a conflict between this standard and other reference documents, the requirements contained within this standard shall govern. The basic wind speed and seismic design category shall be determined in accordance with the applicable building code, or, in the absence of an applicable building code, ASCE 7. For use in this standard, the basic wind speed, as determined by the applicable building code, shall be converted in accordance with Table A1-3. This standard shall include Sections A through F inclusive. A1.1 Limits of Applicability [Note: Delete the fourth paragraph in Section A1.1, as shown below.] This standard shall be limited to buildings meeting the limitations set forth in Table A1-1. In high seismic areas, the limits of applicability of this standard shall be modified as shown in Table A1-2. Detached one and two family dwellings classified in Seismic Design Category E, but meeting the limitations for a regular building and having no floors cantilevering past exterior walls, shall be permitted to be designed in accordance with the requirements for Seismic Design Category D 2. Where building codes or local ordinances regulate building construction based upon fastest mile wind speed, the equivalent basic wind speed (3 sec. gust) shall be determined by Table A1-3. In high seismic areas, buildings in locations with ground snow loads greater than 30 psf (1.44 kn/m 2 ) and with either a normal weight roof/ceiling assembly or light weight roof/ceiling assembly, shall be constructed in accordance with the requirements for buildings with a heavy weight roof/ceiling assembly.

10 2 AISI S230-07/S3-12 [Note: Replace Table A1-3, as shown below.] Table A1-3 Equivalent Basic Wind Speeds () 1 Fastest Mile Second Gust For SI: 1 = 1.61 km/hr = m/sec 1 Linear interpolation is permitted. Table A1-3 Conversion of ASCE 7 Basic Wind Speeds to AISI S230 Basic Wind Speeds () 1 ASCE 7 Basic Wind Speed AISI S230 Basic Wind Speed For SI: 1 = 1.61 km/hr = m/sec 1 ASCE 7 permits linear interpolation between the contours of the basic wind speed maps. A2 Definitions [Note: Revise the definitions for basic wind speed and seismic design category, as shown below.] Basic Wind Speed. The 3-second gust wind speed in accordance with the applicable building code or in absence of a building code in accordance with ASCE 7. Seismic Design Category (SDC). A classification assigned to a building based upon its importance and the severity of the design earthquake ground motion at the building site as given in the local building code or, where there is no building code, as given in ASCE 7. A3 Referenced Documents [Note: Update the list of referenced documents, as shown below.] 1. AISI S100-07, North American Specification for the Design of Cold-Formed Steel Structural Members, American Iron and Steel Institute, Washington, DC. 2. AISI S , North American Standard for Cold-Formed Steel Framing General Provisions, American Iron and Steel Institute, Washington, DC. 3. AISI S , North American Standard for Cold-Formed Steel Framing Product Data, American Iron and Steel Institute, Washington, DC. 4. AISI S , North American Standard for Cold-Formed Steel Framing Truss Design, American Iron and Steel Institute, Washington, DC. 5. ASCE 7-05 Including Supplement 1 ASCE 7-10 Including Supplement 1, Minimum Design Load for Buildings and Other Structures, American Society of Civil Engineers, Reston, VA. 6. ASTM A , Standard Specification for Carbon Steel Bolts and Studs, PSI Tensile Strength, ASTM International, West Conshohocken, PA. 7. ASTM Standard A653/A653M-06a-11, Standard Specification for Sheet Steel, Zinc Coated (Galvanized) or Zinc-Iron Alloy Coated (Galvannealed) by the Hot Dip Process, ASTM International, West Conshohocken, PA.

11 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition 3 8. ASTM Standard A792/A792M-06a-10, Standard Specification for Steel Sheet, 55% Aluminum- Zinc Alloy Coated by the Hot Dip Process, ASTM International, West Conshohocken, PA. 9. ASTM A1003/A1003M-05-11, Standard Specification for Sheet Steel, Carbon, Metallic and Non- Metallic Coated for Cold-Formed Framing Members, ASTM International, West Conshohocken, PA. 10. ASTM C645-07, Standard Specification for Nonstructural Steel Framing Members, ASTM International, West Conshohocken, PA. 11. ASTM F , Standard Specification for Anchor Bolts, Steel, 36, 55, and 105-ksi Yield Strength, ASTM International, West Conshohocken, PA. 12. CSA O (R2003) O Including Update No. 1 (2008), Construction Sheathing, Canadian Standards Association, Mississauga, Ontario, Canada. 13. CSA O437-Series-93 (R2006), Standards on OSB and Waferboard, Canadian Standards Association, Mississauga, Ontario, Canada. 14. DOC PS , Structural Plywood, United States Department of Commerce, National Institute of Standards and Technology, Gaithersburg, MD. 15. DOC PS , Performance Standard for Wood-Based Structural-Use Panels, United States Department of Commerce, National Institute of Standards and Technology, Gaithersburg, MD. A4 Limitations of Framing Members A4.1 General [Note: Update the whole section as shown below.] Structural and non-structural framing members Structural members and nonstructural members shall comply with AISI S201 and the additional limitations of this section. Such limitations shall not apply where design is provided by a design professional. Sheet steel that is in compliance with the requirements of ASTM A653 Type SS or ASTM A792 Type SS shall be deemed to comply with the material specification requirements of AISI S201 and this standard. A4.3.1 Material Properties in High Wind Areas and High Seismic Areas [Note: Update the first paragraph as shown below.] Wall studs and track used in the construction of braced walls in high seismic areas shall be of ASTM A1003 Structural Grade 33 (Grade 230) Type H steel for members with a designation thickness of 33 or 43 and A1003 Structural Grade 50 (Grade 340) Type H steel for members with a designation thickness equal to or greater than 54.

12 4 AISI S230-07/S3-12 CHANGES TO CHAPTER B. CONNECTIONS [Note: Revise red marked values in Tables B2-1 through B2-4 as shown on the next pages.]

13 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition 5 Table B2-1 Clip Angle Bearing Stiffeners 20 psf Equivalent Snow Load Minimum Thickness (Mils) of 2-inch x 2-inch (50.8 mm x 50.8 mm) Clip Angle Joist Designation Top Floor Bottom Floor in 2 Story Middle Floor in 3 Story Bottom Floor in 3 Story Joist Spacing (inches) Joist Spacing (inches) Joist Spacing (inches) S S S S S S S S S S S S S For SI: 1 mil = mm. Table B2-2 Clip Angle Bearing Stiffeners 30 psf Equivalent Snow Load Minimum Thickness (Mils) of 2-inch x 2-inch (50.8 mm x 50.8 mm) Clip Angle Joist Designation Top Floor Bottom Floor in 2 Story Middle Floor in 3 Story Bottom Floor in 3 Story Joist Spacing (inches) Joist Spacing (inches) Joist Spacing (inches) S S S S S S S S S S S S S For SI: 1 mil = mm.

14 6 AISI S230-07/S3-12 Joist Designation Table B2-3 Clip Angle Bearing Stiffeners 50 psf Equivalent Snow Load Minimum Thickness (Mils) of 2-inch x 2-inch (50.8 mm x 50.8 mm) Clip Angle Top Floor Bottom Floor in 2 Story Middle Floor in 3 Story Bottom Floor in 3 Story Joist Spacing (inches) Joist Spacing (inches) Joist Spacing (inches) S S S S S S S S S S S S S For SI: 1 mil = mm. Table B2-4 Clip Angle Bearing Stiffeners 70 psf Equivalent Snow Load Minimum Thickness (Mils) of 2-inch x 2-inch (50.8 mm x 50.8 mm) Clip Angle Joist Designation Top Floor Bottom Floor in 2 Story Middle Floor in 3 Story Bottom Floor in 3 Story Joist Spacing (inches) Joist Spacing (inches) Joist Spacing (inches) S S S S S S S S S S S S S For SI: 1 mil = mm.

15 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition 7 CHANGES TO CHAPTER E. WALL FRAMING [Note: Replace the fourth and fifth rows in Table E2-1, as shown on the next page.]

16 8 AISI S230-07/S3-12 Table E2-1 Wall to Foundation or Floor Connection Requirements 1 Framing Condition Wind Speed (), Exposure, & Seismic Design Category 2 Wall bottom track to floor per Figure E2-4 Wall bottom track to foundation per Figure E2-1 or E2-2 4 Wall bottom track to wood sill per Figure E2-3 Wind uplift connector strength for 16" stud spacing 3 Wind uplift connector strength for 24" stud spacing 3 Wind uplift connector strength (lbs) 3 5 Stud Spacing (in) B or SDC A,B,C 1-No.8 screw at 12" o.c. 1/2" minimum diameter anchor bolt at 6' o.c. Steel plate spaced at 4' o.c., with 4- No.8 screws and 4-10d or 6-8d common nails 90B 1-No.8 screw at 12" o.c. 1/2" minimum diameter anchor bolt at 6' o.c. Steel plate spaced at 4' o.c., with 4- No.8 screws and 4-10d or 6-8d common nails 100B 85 C 1-No.8 screw at 12" o.c. 1/2" minimum diameter anchor bolt at 4' o.c. Steel plate spaced at 3' o.c., with 4- No.8 screws and 4-10d or 6-8d common nails 110B 90 C 1 No.8 screw at 12" o.c. 1/2" minimum diameter anchor bolt at 4' o.c. Steel plate spaced at 3' o.c., with 4- No.8 screws and 4-10d or 6-8d common nails 100 C < 110 C 2 No.8 screw at 12" o.c. 1/2" minimum diameter anchor bolt at 4' o.c. Steel plate spaced at 2' o.c., with 4- No.8 screws and 4-10d or 6-8d common nails N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R 2 No.8 screw at 12" o.c. 1/2" minimum diameter anchor bolt at 4' o.c. Steel plate spaced at 2' o.c., with 4- No.8 screws and 4-10d or 6-8d common nails 65 lbs per foot of wall length 100 lbs per foot of wall length Roof Span (ft) 24 N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R For SI: 1 inch = 25.4 mm, 1 = 1.61 km/hr, 1 foot = m, 1 lb = 4.45 N. 1 Anchor bolts are to be located not more than 12 inches (305 mm) from corners or the termination of bottom tracks (e.g. at door openings or corners). Bolts are to extend a minimum of 15 inches (381 mm) into masonry or 7 inches (178 mm) into concrete. 2 SDC indicates Seismic Design Category. See Sections E11 through E13 for floor connection requirements in high seismic areas and high wind areas. 3 N/R = uplift connector not required

17 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition 9 4 Foundation anchor straps are permitted, in lieu of anchor bolts, if spaced as required to provide equivalent anchorage to the required anchor bolts and installed in accordance with manufacturer s requirements. 5 Refer to Figure E2-5

18 10 AISI S230-07/S3-12 [Note: Revise red marked values in Tables E3-2a to E3-6a as shown on the next pages.]

19 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition KSI Table E3-2a Stud Thickness 28-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 33 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

20 12 AISI S230-07/S KSI Table E3-2b Stud Thickness 28-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 50 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

21 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition KSI Table E3-3a Stud Thickness 32-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 33 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

22 14 AISI S230-07/S KSI Table E3-3b Stud Thickness 32-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 50 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

23 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition KSI Table E3-4a Stud Thickness 36-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 33 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

24 16 AISI S230-07/S KSI Table E3-4b Stud Thickness 36-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 50 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

25 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition KSI Table E3-5a Stud Thickness 40-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 33 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

26 18 AISI S230-07/S KSI Table E3-5b Stud Thickness 40-Foot Wide Building Supporting Roof and Ceiling Only 1,2,3 Fy = 50 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

27 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition KSI Table E3-6a Stud Thickness 24-Foot Wide Building Supporting One Floor, Roof & Ceiling 1,2,3 Fy = 33 ksi Minimum Stud Thickness (Mils) Wind Speed Stud Member 8-Foot Studs 9-Foot Studs 10-Foot Studs Spacing Size Exp. Exp. (inch) Ground Snow Load (psf) B C For SI: 1 inch = 25.4 mm, 1 psf = kn/m 2, 1 = 1.61 km/hr, 1 foot = m 1 Deflection criteria: L/240 2 Design load assumptions: Second floor dead load is 10 psf (0.48 kn/m 2 ) Second floor live load is 30 psf (1.44 kn/m 2 ) Roof/ceiling dead load is 12 psf (0.58 kn/m 2 ) 3 Building width is in the direction of horizontal framing members supported by the wall studs.

28 20 AISI S230-07/S3-12 E7.3 L-Header [Note: Revise the first sentence in Section E7.3, as shown below.] An L-header shall consist of a cold-formed steel angle with one short leg lapping over the top track of the wall and one leg extending down the side of the wall above window or door openings, as shown in Figures E7-4-5 and E7-6.

29 Supplement 3 to the Standard For Cold-Formed Steel Framing Prescriptive Method for One and Two Family Dwellings, 2007 Edition 21 CHANGES TO CHAPTER F. ROOF FRAMING F3 Roof Rafters F3.4 Roof Rafter to Ceiling Joist and Ridge Member Connection [Note: Revise the second sentence in Section F3.4, as shown below.] Roof rafters shall be connected to a parallel ceiling joist to form a continuous tie between exterior walls in accordance with Figures F2-2 or F2-3 and Table F2-9. Ceiling joists shall be connected to the top track of the structural wall in accordance with Table F2-10, either with 2 the required number of No.10 screws applied through the flange of the ceiling joist or by using a 54 mil (1.37 mm) clip angle with 2 the required number of No.10 screws in each leg. Roof rafters shall be connected to a ridge member with a minimum 2 inch x 2 inch (51x51 mm) clip angle fastened with No.10 screws to the ridge member in accordance with Figure F3-2 and Table F3-3. The clip angle shall have a steel thickness equivalent to or greater than the roof rafter thickness and shall extend the depth of the roof rafter member to the extent possible. The ridge member shall be fabricated from a C-shaped member and a track section, which shall have a minimum size and steel thickness equivalent to or greater than that of adjacent roof rafters and shall be installed in accordance with Figure F3-2. The ridge member shall extend the full depth of the sloped roof rafter cut. F4.4 Hip Framing Connections [Note: Revise the second sentence in Section F4.4, as shown below.] Jack rafters shall be connected to a hip member with a minimum 2 inch x 2 inch (51x51 mm) clip angle fastened with No. 10 screws to the hip member in accordance with Figure F3-1-2 and Table F3-3. The clip angle shall have a steel thickness equivalent to or greater than the jack rafter thickness and shall extend the depth of the jack rafter member to the extent possible. F6 Roof Trusses [Note: Revise the second paragraph of Section F6, as shown below.] Trusses shall be designed and installed in accordance with the Standard for Cold-Formed Steel Framing Truss Design. Trusses shall be connected to the top track of the structural wall in accordance with Table F2-10, either with 2 the required number of No.10 screws applied through the flange of the truss or by using a 54 mil (1.37 mm) clip angle with 2 the required number of No.10 screws in each leg. [Note: Replace the first and fourth rows in Table F2-10, as shown on the next page.]

30 22 AISI S230-07/S3-12 Table F2-10 Roof Framing Fastening Schedule Description of Building Elements Number and Size of Fasteners 1 Ceiling joist to top track of structural wall 1 Roof sheathing (oriented strand board or plywood) to roof rafter or truss Number and Spacing of Fasteners 2 - No.10 screws Each joist No.8 screws 6" o.c. on edges and 12" o.c. at interior supports. (6" o.c. at gable end truss) Gypsum board to ceiling Joists No.6 screws 12" on center Truss to top track of structural wall 1 Gable end truss to endwall top track Roof rafter to ceiling joist and to ridge member Ceiling joist or roof truss to top track of structural wall 2 Ceiling Joist or Truss Spacing (in) No.10 screws Each truss No.10 screws 12" o.c. No.10 screws See Tables F2-9 and F3-3 Roof Wind Speed (), Exposure Span (ft) 100 B 110 B 100 C < 110 C 85 C 90 C Each ceiling joist or roof truss For SI: 1 inch = 25.4 mm, 1 foot = m, 1 psf = kn/m 2 1 Screws are minimum No. 10 unless noted otherwise. 2 Screws are to be applied through the flanges of the truss or ceiling joist or a 54 mil (1.37 mm) clip angle is to be used with 2 No.10 screws in each leg.

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