I was asked to do a wind mit for a single end unit on a 4-unit one story villa. I am new to this, so this is the first time I have done a multi-unit wind mit (again, for a single unit on the end). I am trying to understand how to do the roof calculation for hip/non-hip. Do I treat this as three walls and base the calculation on that? I have recently completed wind mit NACHI course but did not see anything in there that addressed multi-unit roof calculations. Any help would be greatly appreciated.
By the way, here is a pic of the front of the building.
You need to do the roof calculations for the whole roof. The only time this changes is if the unit has a clearly divided roof. (A Parapet wall that clearly separates your unit from the others in the building.)
You will have to do the shape calculation on the entire roof over all units. It is all one roof system. The only thing that is separate from the rest of the building is the opening protection for the unit you are inspecting. The RTW and RDA attachment can be verified in one unit, as this should be the same for all units.
I see approx 48 (6 x 8 ) feet of gable. I seriously doubt there is 480 feet of perimeter. Quickly, lets say 140 across the front, 100 across the back (usually straight hip on back). That means the building would have to be 120 feet deep. I don’t see it.
wow. impressed with how helpful everyone is. thank you very much!
more details:
60’ deep, approx 28’ back roof line, end unit only, with no gable features on back roof or side (depth). Front features I measured 15’ of gable features on the end unit. Not knowing, I did not measure or walk off every roof feature all the way around the structure. I could probably derive some critical info from property appraisers site.
