Jim:
Be aware that this is the design wind pressure at 0' or
0 meter elevation... The US codes specify design wind
velocity at 30' up. The US codes do not start with
design pressure.
Hank Lonberg, P.E.,S.E.
KR7X
> 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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