How do I calculate a capacity for lumber sheathing or heavy timber decking diaphragms?
• AF&PA’s Wood Frame Construction Manual for One- and Two- Family Dwellings, 2001 Edition, Table 3B contains shear capacities for 5/8″ lumber sheathing attached straight and diagonally. Table 3C contains shear wall capacities for straight and diagonal lumber sheathing as well. AF&PA’s Special Design Provisions for Wind and Seismic, ANSI/AF&PA SDPWS-2005 contains nominal unit shear capacities for lumber sheathed diaphragms and shear walls. The SDPWS is available at: http://www.awc.org/Standards/SDPWS.html. AF&PA also publishes Plank and Beam Framing for Residential Buildings (WCD-4) (T14). It shows how this floor and roof framing system, traditionally used in heavy timber structures, can be adapted to home building. The International Building Code contains design capacities for diagonally sheathed lumber diaphragms in section 2306.3 Wood Diaphragms. Visit http://www.iccsafe.org for ordering information. Analysis Methods for Horizontal Wood Diaphragms by Jephcott and Dewdney from proceed
