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The 2010 NBC will provide deflection equations for walls, roofs, and floors, amongst other new structural design provisions aimed at wood structures.

The use of wood in large buildings and homes will be impacted by new structural provisions set forth in the 2010 edition of the National Building Code of Canada (NBC).

Part 4 of NBC specifies structural design requirements for large buildings. Specifications include loads to be considered in design, as well as references to material engineering standards to determine the structural capacity to resist loads.

The 2010 version will refer to the latest edition of Canadian Standards Association (CSA) O86, Engineering Design in Wood, published in 2009. Significant changes in the 2009 CSA O86 include:
• new lateral design provisions for the ability of wood structures to resist wind and earthquake loads;
• new design provisions for wood screws;
• improved design provisions for bolts and nails;
• more efficient design provisions for studs and columns; and
• revised design values for panels, lumber, glue-laminated (glulam) timber, and structural composite lumber.

The latest provisions in the 2010 NBC especially affect new residential construction, which forms the largest market for structural wood products. Part 9 of NBC addresses smaller buildings and housing, prescriptively providing wood construction details. Relevant changes to Part 9 include:
• lateral resistance provisions for housing and small buildings to address high wind and seismic loads;
• reference to new product standards for preservative-treated lumber; and
• reference to the Canadian Wood Council's (CWC's) 2009 Engineering Guide for Wood Frame Construction (for guidance on design elements outside Part 9's prescriptive requirements).