Roof Load Required For Snow

If unbalanced snow loading isn t required or specified the truss designer may enter the 25 psf snow load as a top chord live load tcll set the load duration factor to 1 15 for snow and turn snow loading off completely.

Roof load required for snow.

State snow load information alabama. Or the 25 psf snow load could be entered as a roof snow load with the unbalanced snow loading option turned off. Town load town load aguilar 40 idaho springs 50 alamosa 20 ignacio 40. 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.

In order to stay intact and in place a roof must be able to resist loads both permanent and temporary that are pushing. Recommended basic snow design loads snow loads by city 1. A great deal of confusion currently exists among engineers architects recreation specialists and maintenance personnel concerning the proper snow loading to use for the design and maintenance of trail bridges building roofs and other structures in mountainous high snow load areas. Load limits on the roof of a building.

Modify these basic loads for wind shape of roof drifting ice loads etc. Roofs are under a lot of pressure. If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow. Roof load live load design is affected by the shape of the roof whether it is flat curved or pitched.

Roof loads are a downward vertical force on the home. In areas of the state outside of certified city county and town jurisdictions the design snow load shall be based on the ground snow loads developed in snow loads for structural design in montana civil engineering department montana state university 2004 revised edition. The north zone middle zone and the south zone are identified on the roof load zone. Why snow load information.

Loads are in pounds per square foot. If the snow weighs 10 pounds per cubic foot and there are 1 5 feet on the roof each square foot of the roof is getting 15 pounds of pressure. Table r301 2 1 climatic and geographic design criteria ground snow load. Snow loads shall be determined by the building official.

However a south roof load zone home cannot be installed in either a middle or north roof load zone. Use only within immediate vicinity of given town particularly if ground elevation changes noticeably. Use ibc 2003 25 psf 300 psf and state of alaska has given authority to local building officials for determining required snow loads for their municipalities.