On Thu, 15 Aug 2002 Hank Lonberg wrote:
>The BC code and National Building Code of Canada do not
>use wind velocity. They use a design velocity pressure
>in kPa based on recurrence frequencies of 1 in 10yrs, 1
>in 30yrs, and 1 in 100yrs. The value you seek is the 1
>in 30yr value.
>
>From Appendix C 1998 BCBC, the values for Vancouver,
>including Richmond, Surrey and W. Vancouver are as
>follows:
>
>1 in 10 : 0.36 kPa = 7.72 psf
>1 in 30 : 0.44 kPa = 9.19 psf
>
>You could convert these to mph via p=0.00256*V^2.
>Like all codes the design pressure is modified by
>several factors to account for terrain, gusting and
>height above the ground.
Amazing how the conversion yields almost exactly 55 and 60 mph!
--
Jimmy Weierich, K2LV, ex KG2AU <kg2au@stny.rr.com>
Vestal, NY USA FN12xa
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