Greeley, CO Frost Depth & Snow Load: Roof Snow Load (2026)

Greeley's approach to roof snow load is a two-part rule and both parts matter. The design roof snow load values are to be determined from Section 1608 of the IBC, including all applicable factors and the loading and drifting considerations of Chapter 7 of ASCE 7. That is the normal derivation from the city's 30 psf ground snow load. The ordinance then adds a floor: in no case shall the final design roof snow load be less than a uniformly distributed load of 20 psf. So the calculation can reduce the roof load relative to the ground load, as calculations normally do for sloped and exposed roofs, but it cannot reduce it below 20 psf. That floor is the part most often missed, because it only bites on the cases where the calculation would otherwise produce a low number, steep, exposed, warm roofs.