unusual roof configuration design snow load

huangyhg

unusual roof configuration design snow load
i'm doing a office condo building in colorado springs that has a condition i've not encountered before. most of it is pretty normal, rectangular shape, 138'x66', 4/12 slope hipped roof, asphalt shingles, pg=20 psf, pf=30 psf, 2003 ibc. the unusual part is a flat area, approx. 67'x20', in the center where the mechanical units will go. this flat area is located down around truss bearing, well below peak of sloped roof. the roof at east and west ends peaks and slopes down to flat area. the north and south sides are the vertical face of the truss heels, approx. 8' high. this creates a snow pit that i feel is not covered by asce 7 or 2003 ibc. what snow load do i design the flat roof joists for?
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this is potential snow drift area.
check the drift loads from each direction (windward/leeward).
check additional sliding snow from sloped roof.
i hate this kind of thing because someone always jumps on me for "greatly oversizing" the members under the pit.
as sperlingpe said, it does seem like the drift and sliding snow loads from the asce 7 should cover you, if i understand the configuration. the load might be substantial.
just out of curiosity, how is this hole drained? i am reminded of the roof drainage thread from a couple of weeks ago.