FullCalculator

Snow Load Calculator

Basic Snow Load

Calculate snow load from depth and snow type

Ground-to-Roof Conversion

Convert ground snow load to roof snow load using exposure factor

Formula

Snow Load (psf) = Snow Density (lb/ft³) × Depth (ft) | Roof Load: pf = 0.7 × Ce × Ct × Is × pg

Frequently Asked Questions

How much does snow weigh per square foot?
It varies by type: fresh fluffy snow weighs 3-5 lbs per sq ft per foot of depth, settled snow 15-20 lbs, packed snow 20-30 lbs, and wet heavy snow 30-40 lbs. Ice weighs about 57 lbs per cubic foot.
When should I remove snow from my roof?
Consider snow removal when loads approach 20 psf (about 4 feet of light snow or 2 feet of heavy wet snow). Warning signs include creaking sounds, sagging, cracks in walls or ceilings, and doors that stick.
What is the ground snow load for my area?
Ground snow loads are specified in ASCE 7 and local building codes. They range from 0 psf in southern states to over 100 psf in mountainous areas. Common values: Boston 40 psf, Chicago 25 psf, Denver 25 psf, Minneapolis 50 psf.

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