Snow Load Calculator — Roof Load in psf & lbs

How the snow load calculator works

Snow load in psf = (depth in inches ÷ 12) × density (lb/ft³). Multiply by roof area to get total load in pounds. Fresh snow ≈ 7 lb/ft³, settled ≈ 15, packed/wet ≈ 20+.

Frequently asked questions

How much does 1 foot of snow weigh?

Fresh dry snow ~7 psf, settled snow ~15 psf, wet or packed snow can exceed 20 psf per foot of depth.

When should I remove snow from my roof?

If snow depth × density approaches the roof's design snow load (often 20–40 psf depending on region), rake or shovel.

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