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canopy wind loads

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Don,
I have discussed this subject until I am blue in the face with many engineers and on this list. Essentially, to my understanding, "the canopy" is not a structure with thorough testing, so it really is a judgement call.
 
So IMHO:
If you take a canopy away from a building, like a gas station canopy, that is an open structure. Use ASCE open structure wind loads. But what if it has a parapet or fascia that is 5ft or so deep? Well I use sign wind loads from ASCE, others use wall pressures for closed buildings. I think the fascia/parapet will behave much like a free standing sign.
 
Push this canopy near a building like a hotel drive-thru. As it gets closer to the building it begins to behave more like an overhang, which recieves wind pressure underneath as the wind rushes into the wall, goes up the wall, then pushes against the soffit/overhang. It also recieves wind uplift like an airplane wing as the wind rushes over top of it. Now if you have a 200' wide building with a long, narrow canopy, say 20' wide framing into it like at a school, I say within 10-20 feet of the building it will recieve overhang type wind loads, then away from the building it will recieve regular open building loads. As I see it, as the roof moves away from the wall, there is more room and open area for the wind to "escape" and relieve this underneath wind pressure.
 
On a side note, the metal scrap yard in downtown Orlando has piles 40 feet high of aluminium roofing, siding, canopies, pool enclosures, etc. On the other hand, the Detmer or similiar brand canopies on all of our schools have done excellent. Also, they estimate that in Central FL in the last 8 weeks, the amount of tree debris amounts to the same as the previous 10 YEARS!
 
Andrew Kester, PE
Longwood, FL