Component and Cladding Load ASCE 7-05

[cgstrucg]

Hello,

I am working on a project which has 3 different elevation flat roofs. All roofs are connected to each other. I got uplift and downward wind pressures for the individual roofs. My question is this - While considering roof joist members for component and cladding wind loads, shall I consider individual roof corners to be in zone 2 and 3 or can I consider them stepped roofs and consider intersecting members to be in a lower zone.

If I can consider it as a stepped roof then I have an intersection which is less then 10ft. ASCE states zone reductions for height greater than 10ft. What shall I consider for heights less than 10ft?

Thanks a lot for the help.

 

[flight7]

I don't understand the configuration you're describing. Can you post a sketch? If the height difference is less than 10 feet then you can't take any reductions.

 

[cgstrucg]

See attached. That's what I thought that we can't apply reductions and would have to consider each corner as zone 2 and 3.

Also, I see the table is for h>60'. What if my building height is more then 60ft but the lower roof is less than 60ft like around 45ft. I don't see any commentary mentioning any reductions in that case either.