Roof Support Snow Load Wisconsin

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 support snow load wisconsin.

Other considerations for sloped roofs can be found throughout chapter 7 of asce 7 10. How much snow a roof can hold depends on the type of snow roofline and material among other considerations. Wisconsin has not adopted the international residential code irc and utilizes its own uniform dwelling code udc for all residential structures. 2002 wisconsin enrolled commercial building code.

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. It goes without saying that in a warmer climate the snow load probably would be less so you need to check your code book for live loads and dead loads in your region. The flat roof snow load is calculated using formula 7 3 1. Our sample homes are in an area where the snow load is 50 pounds per square foot of roof area treat snow as live load.

Use our wisconsin roof snow loads map to easily determine the roof design snow load wisconsin administrative code. Sps 321 02 1 c c wind loads. In addition to estimating the roof loading it s important to know the loading the roof can resist. Snow loads roofs shall be designed and constructed to support the minimum snow loads listed on the zone map.

In our case let s assume that our structure has a flat roof roof slope 5. H load due to lateral pressure of soil and water in soil. Or the 25 psf snow load could be entered as a roof snow load with the unbalanced snow loading option turned off. Wisconsin s uniform dwelling code requires most homes to have a minimum snow load rating of 30 40 pounds per square foot lbs ft 2 with the greater requirement for northern wisconsin.

The loads shall be assumed to act vertically over the roof area pro jected upon a horizontal plane. L roof live load including any permitted live load reduc tion. The snow load that is applied to our structure is not the ground snow load but in most cases the flat roof snow load. If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow.

Agricultural structures are exempt from this requirement. Dwellings shall be designed and constructed to withstand either a horizontal and uplift pressure of 20 pounds. 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. Roofs shall be designed and constructed to support the minimum snow loads listed on the zone map.

L live load except roof live load including any per1nit ted live load reduction. You can click on the map below to find the minimum roof design snow load for that location.