Weight Of Wet Snow On Roof

Use this basic formula as a guide but always check with your local weather experts regarding the type of snow that.

Weight of wet snow on roof.

The roof deck collects the snow load and transfers the weight to the rafters. Max weight 4195 lbs. Estimate the weight of snow on your roof saturated snow weighs about 20 lbs cubic foot. It is also important to remember that that math doesn t take into account any ice you have on your roof which weighs much more than heavy wet snow weighs.

2 2 1 range in snow weight the weight of 1 foot of fresh snow ranges from 3 pounds per square foot for light dry snow to 21 pounds per square foot for wet heavy snow. Start by finding the volume. 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. S 1 25 p where s is the number of inches of snow on your roof and p is the pounds per.

It could weigh over 20 pounds if it s wet and compacted. Volume 1 12 14. Max weight 24 97 lbs 168 cu. Even old stick trusses are designed to carry a load on your roof of about 40 lbs.

So while a cubic foot of fresh powder might weigh in at 7 pounds that same amount of wet packed snow could be more like 20. For an average size roof about 2000 square feet covered in heavy wet snow a good rule of thumb is the weight of one compact suv 3 470 lbs on your roof for every 1 inch of snow. Heavy snowfall accumulation will stress your roof and may potentially become a danger to roof collapse design dependent. Min weight 3670 8 lbs.

This snow probably weighs about four pounds per cubic foot. Min weight 21 85 lbs 168 cu. Snow density increases over time as the snow experiences more changes in temperature and wind. Snow density is a function of temperature wind exposure and time.

Wind packed snow has a density of 21 85 to 24 97 pounds per cubic foot. A cubic foot of snow can weigh about 7 pounds if it s dry and fluffy. Wet snow can be nearly three times heavier than dry fluffy snow. Two feet of snow on a roof with a footprint of say 28 40 feet could weigh 45 000 pounds.

Using the chart above find the density.