On the other hand snow that stayed on your roof for a few days will settle and while it seems that the cover gets thinner its weight doesn t change it s just the density that is different.
Roof load psf.
Roof loads are a downward vertical force on the home.
The minimum design roof snow load after allowed reductions shall be 30 psf.
Here each square foot of roof system delivers 50 pounds of live load and 15 pounds of dead load 65 psf total to the structural support system.
For example fresh snow is soft fluffy and light.
C plf pounds per lineal foot is used to describe loads on walls or long members such as beams.
Remember these loads are distributed uniformly over the entire surface of the roof.
The north zone middle zone and the south zone are identified on the roof load zone map above.
The load increases with the use of heavier roofing material.
B psf pounds per square foot is used to describe loads on flat surfaces such as floors and roofs.
Location 2uniform load psf kn m roofs ordinary flat pitched and curved roofs roofs used for roof gardens roofs used for assembly occupancies roofs used for other occupancies awnings and canopies fabric construction supported by a skeleton structure screen enclosure support frame.
To total the load on an area multiply the area times the psf.
However if the attic is intended for storage the attic live load or some portion should also be considered for the design of.
Roof load live load design is affected by the shape of the roof whether it is flat curved or pitched.
Each square foot of the surface has the same load.
The following table provides typical weights dead load self weight for various roofing materials where possible the values were taken directly from manufacturer technical data sheets and are the actual weights of specific representative products.
In areas of the state outside of certified local government jurisdictions the design snow load shall be based on the ground snow loads developed in snow loads for structural design in montana authored by f f.
The density of snow and hence its load per square foot depends on the type of snow.
A clay tiled roof may have a dead load.
2attic loads may be included in the floor live load but a 10 psf attic load is typically used only to size ceiling joists adequately for access purposes.