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Re: ASCE7-98 Wind Loads for Cladding

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Look under 6.5.12.4. The equations and definitions given there will, I believe,
clear all this up for you.

Basically, the distinction is that you MAY simply (and conservatively) use qh,
based on the mean roof height, for calculating the wind pressure for components
and cladding when the building is 60 feet or less in height, for all wind
directions; but you MUST use qz evaluated at the level of the component you are
loading, when the building height is greater than 60 feet, and when the
component is on the "windward" side.

I hope that was clear.

"Jones, Mark A (Battle Creek)" wrote:
> 
> The difference between the two paragraphs are the words "using a velocity
> pressure qh based on the".   Does anyone have a clarification?  Does this
> mean that I don't use the velocity pressure, qh, in structures greater than
> 60 ft?  Since the rest of the design procedure is based on qh, this doesn't
> make since.  If I read it knowing that I have to use qh, then there is no
> difference between the two paragraphs.