Minimum Roof Pitch For Michigan Snow Loads

You can click on the map below to find the design ground snow load for that location.

Minimum roof pitch for michigan snow loads.

The state has amended the snow load requirements of the 2009 ibc figure 1608 2 and the 2009 irc figure r301 2 5 table r301 2 1 and table. If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow. The chief reason for having a roof pitch is to redirect water and snow away from the roof and avoid any percolation that might result from stagnation of water on the roof. Run in degrees and as percentage the minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.

Importance of a roof pitch. Roof slope equivalents as rise. To figure out the load on your roof take the depth of snow in feet and multiply it by the weight of a cubic foot of snow. The key factors are usually snow loading requirements adequate slope and the use of snow guards when needed.

If these issues are addressed during the design stage and the roofing contractor does his job these systems will almost always perform as intended. Roof pitch multiplier table. In general determining the pitch of an existing roof is a simple calculation. If you live in the us our snow load calculator compares the total weight on your roof with the permissible load calculated according to the standards issued by the american society of civil engineers regarding the minimum design loads for buildings and other structures asce7 16.

The minimum roof pitch is also subject to the standards set forth by the various building codes used in the respective regions. Astm b209 0 024 minimum thickness for roll formed panels and 0 019 inch minimum thickness for press formed shingles. 12 oz sq ft for preformed metal shingle systems. For example a roof with a 6 inch 12 pitch is one where it rises 6 inches vertically for every 12 inches of the horizontal run.

Degrees to pitch rise in run table. Figure 1608 2 for any location in the state of michigan. Use our michigan ground snow loads map to easily determine the ground snow load 2009 michigan building code. This can be accomplished by measuring the number of inches the roof rises vertically for every 12 inches it extends horizontally.