Roof Slope For Snow Load

As i design roofs today in ski resort areas i use one of the above types of roofs and plan to keep the snow on.

Roof slope for snow load.

The sloped roof snow load p s shall be obtained by multiplying the flat roof snow load p f by the roof slope factor c s. Sloped roof snow loads are assumed to be acting on the horizontal projection of the surface. P s c s p f the thermal factor c t from table e 3 determines if a roof is cold or warm slippery surface values shall be used only where the roof s surface is unobstructed and sufficient space is available below the eaves to accept all the sliding snow. If you live in a climate with cold winters and numerous snow storms a pitched roof will prevent the snow from remaining on the top of your home.

The sloped roof snow load is calculated using equation 7 4 1. 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 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. Our approach in north america is to use a metal roof with a steep slope that will allow the snow and ice to slide off.

When the roof slope is greater than 5 the roof is considered sloped. If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow. P s c s p f. The steeper the pitch the better the snow will fall to the ground.

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.