Snow Load On Roof Trusses

Overestimation of snow loads can unnecessarily increase the cost of construction.

Snow load on roof trusses.

You can enter these values in any units you d like including meters and feet. If a roof is subjected to snow load it should be designed for the actual loads due to snow or for the live loads specified above whichever is more severe. Dol can play a part in some snow areas where the building official bo has made the determination snow will remain upon the roof for extended time periods. The information provided here is not intended to replace truss drawings.

Actual load due to snow will depend upon the shape of the roof and its capacity to retain the snow and each case shall be treated on its own merits. To calculate the weight of snow on a roof use the first two sections of our snow load calculator. Snow loads are influenced by elevation general weather and moisture patterns slope direction exposure roof or trail bridge configuration and wind direction and severity. If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow.

The current snow load criteria irc 2012 2015 r301 2 3 irc 2012 2015 figure r301 2 5 ibc 2012 2015 1608 begins with a base value i e. Trusses are designed to carry two types of loads. Live loads include wind precipitation foot traffic and all other weight that comes and goes. The top chord live load tcll of any roof trusses will be the greater of pr or lr.

This web based application is made freely available courtesy of the advertisements displayed on this page. Ground snow load to which several modification factors are applied. A live load is a temporary load that puts stress on the structure. Live loads and dead loads.

Duration of load dol for snow is typically 1 15. The snow load calculations provided by this online tool are for educational and illustrative purposes only. A dead load is carried constantly by the truss. Medeek design assumes no liability or loss for any designs presented and does not guarantee fitness for use.

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. Engineered truss drawings should be obtained for specific site locations incorporating specific snow load wind speed eave wall height building length and importance factor use of building. 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. Lengthand widthof your roof.