Local codes and ammendments may govern verify with local building department or jurisdiction.
Montana ground snow load to roof converter.
In our case let s assume that our structure has a flat roof roof slope 5.
If you live in the us our snow load calculator compares the total weight on your roof with the permissible load calculated according to the standards issued by the american society of civil engineers regarding the minimum design loads for buildings and other structures asce7 16.
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.
The state of montana requires a minimum roof snow load of 30 psf be used for design 2 this minimum value applies to the final roof snow load that is calculated after all coefficients have been applied and it may be revised when justified by a design professional to the satisfaction of the building official.
Snow loads shall be determined by the building official.
Ground snow load s s.
Roof snow load nbc 2010 version 0 1 0 september 13 2020.
Pursuant to montana law the minimum design roof snow load after allowed reductions shall be 30 psf.
Note that the state of montana requires a minimum roof snow load of 30 psf be used for design.
Local and or state requirements on the ground snow loads or the roof loads subsequently calculated from these values supercede the values provided by this snow load finder tool.
Importance factor i s.
The flat roof snow load is calculated using formula 7 3 1.
All of the load cases required to fully design an actual structure are not provided by this calculator.
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.
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.
Specified snow load.
Or the 25 psf snow load could be entered as a roof snow load with the unbalanced snow loading option turned off.
If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow.
The snow load that is applied to our structure is not the ground snow load but in most cases the flat roof snow load.
Other considerations for sloped roofs can be found throughout chapter 7 of asce 7 10.
R802 10 2 and designed according to the minimum requirements of asce 7 10.
Note that the state of montana requires a minimum roof snow load of 30 psf to be used for design regardless of ground snow load.
Ground snow loads derived from montana ground snow load finder.
