Canopy Snow Drift

[KHoff]

I am reviewing calculations for the design of a 5 ft cantilevered canopy on the side of a building (see attached for a wall section). The building is a large warehouse, so there is potential for significant snow drift based on the length of roof. The engineer who designed the canopy is assuming that there is not any snow drift on the canopy because the height of the drift is less than the height of the parapet, essentially saying that the parapet blocks all drift on the canopy. I don't believe the code allows this assumption, and in my opinion it is a bad assumption as I have seen significant snow drift on these types of canopies. Can anyone provide direction regarding where this assumption might be coming from? Anything in the code or other references?

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1575309328/tips/07057002-2-A402_gxa5g3.pdf[/url]

 

[KHoff]

See attached for snow drift calc.

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1575309505/tips/M4325_-_STAMPED_FF_CALCS_-_02-19-19-_SEC_2071-18_ijk617.pdf[/url]

 

[JAE]

Review this - a recent thread on the same topic.
thread507-460889