Roof Support Snow Load Wisconsin
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.
Roof support snow load wisconsin. L roof live load including any permitted live load reduc tion. In our case let s assume that our structure has a flat roof roof slope 5. 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. Other considerations for sloped roofs can be found throughout chapter 7 of asce 7 10.
H load due to lateral pressure of soil and water in soil. Snow loads roofs shall be designed and constructed to support the minimum snow loads listed on the zone map. Sps 321 subchapter 2 for any location in the state of wisconsin. Or the 25 psf snow load could be entered as a roof snow load with the unbalanced snow loading option turned off.
L live load except roof live load including any per1nit ted live load reduction. Agricultural structures are exempt from this requirement. 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.
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. Sps 321 02 1 c c wind loads. Wisconsin has not adopted the international residential code irc and utilizes its own uniform dwelling code udc for all residential structures. How much snow a roof can hold depends on the type of snow roofline and material among other considerations.
The loads shall be assumed to act vertically over the roof area pro jected upon a horizontal plane. The loads shall be assumed to act vertically over the roof area projected upon a horizontal plane. In addition to estimating the roof loading it s important to know the loading the roof can resist. Roofs shall be designed and constructed to support the minimum snow loads listed on the zone map.
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. Dwellings shall be designed and constructed to withstand either a horizontal and uplift pressure of 20 pounds. If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow. 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 flat roof snow load is calculated using formula 7 3 1. The snow load that is applied to our structure is not the ground snow load but in most cases the flat roof snow load.