Question about wind loading on open canopy attached to a building. 1

[brTCP]

I have a horizontal canopy attached to a building, as shown in the figure below. The canopy does not have any cladding except for some timber joists. The idea of this canopy is to create some shadow, nothing more. The solid area divided by the total area of the canopy is about 0.4 (taking into account the timber joists). I am wondering how I should deal with wind loading in this case. I didn't find a clear reefrence in Eurocode 1-4 about this situation (low solidity ratio, about 0.4, horizontal canopy attached to a building). What do you recommend? Should I treat it as a flat roof in a regular building, a canopy, sth else? What is your experience with these kind of structures?

Ideally, I am looking for an answer based on Eurocode, but your reply is welcome if your reply is based on another code. Thanks!

 

[phamENG]

No idea about Eurocode, but ASCE 7 added a section for this sort of canopy if it's solid. It considers the flow of air up and down the building, pressure build up below, etc. And, frankly, I would design it as if it were solid. This is the sort of thing, especially if it's wood, that it's way too easy for somebody to realize they want a little rain protection at the entry, or more shade at some window, and slap some plywood and a membrane on it.

So given the ease with which it can be converted to a solid canopy and the lack of good methods that deliver a lower loading value, I'm inclined to use what I have and provide the more conservative design. It's a canopy. Not worth risking my reputation/license on it not performing properly.