Minimum Roof Pitch For Snow Loads

The sloped roof snow load is calculated using equation 7 4 1.

Minimum roof pitch for snow loads.

All commercial buildings and structures should use the ground snow load values from the 2009 ibc and not the residential design values given below. Sloped roof snow loads are assumed to be acting on the horizontal projection of the surface. You can click on the map below to find the minimum roof design snow load for that location. Begin by measuring 12 inches on your level and marking it with a pencil.

P s c s p f. A minimum slope of 1 inch per foot is recommended in snow country. The key factors are usually snow loading requirements adequate slope and the use of snow guards when needed. You can safely measure the roof pitch from inside your attic with a level that is either 18 or 24 inches a tape measure and a pencil.

When the roof slope is greater than 5 the roof is considered sloped. The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code. Metal roofing systems have a good track record of performance in harsh winter environments as long as they are properly designed.