In continuing its efforts to promote the use of steel framing, the Cold-Formed Steel Engineers Institute (CFSEI), the technical council of the Steel Framing Alliance (SFA) has developed another resource - the first CFSEI Design Guide: Cold-Formed Steel Framed Wood Panel or Steel Sheathed Shear Wall Assemblies (Shear Wall Design Guide). With the imminent release (March 2009) of the International Codes, this guide will allow engineers, specifiers, and architects to better understand the latest code requirements with respect to lateral design with cold-formed steel, and in particular how shear wall applications can be incorporated into designs with the new codes. Examples in the new Shear Wall Design Guide are based on AISI S213-07: Standard for Cold-Formed Steel Framing – Lateral Design, which is referenced by chapter 22 of the 2009 International Building Code (IBC).

The guide contains information about design of lateral resisting elements for walls in buildings with cold-formed steel framing (CFSF). Lateral resisting elements are required in all buildings, but in light-frame construction, shearwalls tend to be the most economical method for transferring loads imposed by wind and earthquakes. The Shear Wall Design Guide addresses all levels of wind and seismic resistance, including the special detailing required in high-seismic areas.

Section 1 of the guide provides basic information and background on the design of shearwalls and use of referenced standards. The majority of the document is in sections 2 through 4 which contain a series of examples dedicated to designing shear wall assemblies and force-transfer elements in a two story office building. These include building specific detailing issues such as connections through a wood panel horizontal diaphragm, collector and collector connection design, design of chord studs and hold-downs, and calculating shear wall deflection. Wherever code references or exceptions are used, the particular location in the code is cited, including equation numbers, figure and table references, and even footnotes to tables that can have an effect on design loads and requirements.

The primary author of the Shear Wall Design Guide is Jeff Ellis, P.E. S.E., of Simpson Strong-Tie Co., Inc. Ellis is the immediate past President of CFSEI, and chairs the American Iron and Steel Institute (AISI) Committee on Framing Standards (COFS) Lateral Design Subcommittee. The Lateral Design Subcommittee is responsible for the development of AISI S213-07: Standard for Cold-Formed Steel Framing – Lateral Design. S213-07, as well as ASCE 7-05 Minimum Design Loads for Buildings and Other Structures, are referenced heavily within this document. ASCE7-05 and the 2004 Lateral Design standard are referenced in the 2006 International Building Code (IBC) and ASCE7-05 and AISI S213-07 are referenced by the upcoming 2009 IBC.

The Shear Wall Design Guide will be available soon from the CFSEI / SFA online store. To buy a copy of the guide please visit http://store.steelframingalliancestore.com/costfrwoorst.html

As with all CFSEI and SFA publications, members receive a 25 per cent discount off of the cover price. ($30 for members, $40 for non-members)

CFSEI will have copies of this document available for review at some of their upcoming chapter meetings, as well at the CFSEI Annual Meeting April 1-2, 2009 in Anaheim, California. At Anaheim, some of the Design Guide examples will be included in the technical presentations sponsored by the CFSEI West chapter.

Don Allen, Director of Engineering, Steel Framing Alliance