Canadian Building Code

[spats]

I'm doing some preliminary design for a building in Canada, and I am not familiar with the Canadian Code. I'm having difficultly with two items:

1. Snow load: In Part 4 of the 2006 Building Code,there is a Ca (shape factor) applied to the snow load that is equal to 1.0, except for drifting/sliding snow areas, valleys, at roof projections, etc. However, I can't find anything about calculating Ca for these exceptions. My interest is in drifting/sliding snow. How do you calculate drifts for the Canadian Code?

2. Wind load: 4.1.7 tells you how to calculate external & internal pressures and suctions, but it is unclear to me how you combine them for the building as a whole (MWFRS), for primary members, and for components. When I add the external and internal numbers, I get very large pressures, and the wind pressure for my particular city is q = 0.54kPa, which equates to only about 65 mph. The key seems to be 4.1.7.1(2) and 4.1.7.1(3), but I can't make heads or tails of it.

Any insight or a design example from somebody who is familiar with the Code would be greatly appreciated.

 

[gwynn]

Do you have the Commentaries on the NBCC or just the NBCC itself? Both of these are addressed in the Commentaries.

 

[SkiisAndBikes]

Both your questions are addressed in the Users's Guide - NBC 2005, Structural Commentaries prepared by the National Research Council of Canada. As there are many different scenario's, likely best if you pick up a copy.

 

[spats]

Thanks to both... just what the doctor ordered! I was unaware of this document.