ASCE Wind Loads - Enclosure and Internal Pressure.

[VirL]

Can a building be considered both partially enclosed and enclosed? When where I see it, the A0 in the formulas, is the openings area in the windward wall, and in that case I could have a different classification for each direction. In the image i show, i think i should consider and internal pressure coefficient of +0.55 in the first case, and -0.18 in the second.
I can´t find any reference that clarify this. Any help would be much appreciated.

 

[Ganesh Persaud]

You should check the percentage of opening on each wall. Check to see if it's not an open building concept having more than 80%. My answer to your question, however, is no, where you have the opening to the windward direction, you have a high positive internal pressure and when the opening is to the leeward side, you have a high negative internal pressure. I would say treat it as partially enclosed.

 

[EDub24]

Full disclosure.I'm in seismic country so for most structures are controlled by earthquakes and I only do a cursory check of wind. With that said I think you could potentially have different enclosure classifications depending on which way the wind is blowing (pun intended). The enclosure check is for walls with positive pressure which would be the windward wall while the sidewalls and leeward wall would have negative pressure. with that rational you could have different enclosure classifications depending on which wall is the windward wall. That can be a organizational nightmare though and most engineers I know just take the worst case.