Enter your Snow Type, Snow Thickness, Roof Length, Roof Width, and Roof Pitch into the Snow Load Calculator to find the Total Snow Weight pressing down on your roof, plus Snow Load, Snow Density, and Roof Area — so you know exactly how much your structure is holding before that next big storm hits.
Total Snow Weight
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Snow Load
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Snow Density
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Roof Area
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The weight of snow on a roof depends on the snow type and thickness. Fresh snow weighs about 5-12 lbs/ft³, while wet snow can weigh 15-20 lbs/ft³. A foot of wet snow can add 15-20 pounds per square foot to your roof.
You should remove snow if the total load exceeds your roof's design capacity, typically 20-30 lbs/ft² for residential roofs. Look for warning signs like sagging, creaking sounds, or cracks in walls or ceilings.
Different snow types have varying densities. Fresh powder snow is lightest at 5-12 lbs/ft³, while very wet snow can reach 15-20 lbs/ft³. Wind-packed and settled snow fall between these ranges.
Watch for sagging roof lines, cracking sounds from the structure, doors or windows that stick, cracks in drywall or masonry, and severe ice dams. These indicate your roof may be overstressed.
Use a roof rake from the ground when possible, remove snow in small sections, avoid getting on the roof yourself, and consider hiring professionals for steep or high roofs. Never use metal tools that could damage roofing materials.
Yes, steeper roofs shed snow more easily, reducing the actual load. Roofs with slopes greater than 30° typically don't retain significant snow loads, while flat roofs bear the full weight of accumulated snow.