Estimate flat roof snow load, sloped roof snow load, total snow weight, rafter line load, beam line load, and support reactions. Use this snow load calculator for roof beams, rafters, ridge beams, headers, posts, footings, and preliminary structural planning.
Flat roof snow load:
The calculator uses ground snow load with exposure, thermal, and importance factors to estimate flat roof snow load.
Sloped roof snow load:
The calculator multiplies flat roof snow load by the roof slope factor and adds drift or surcharge loads when entered.
Rafter line load:
The calculator multiplies snow load PSF by rafter spacing to estimate the load on each rafter.
Beam line load:
The calculator multiplies snow load PSF by tributary width to estimate the snow load carried by a beam or header.
A snow load calculator helps estimate roof snow weight before checking rafters, beams, ridge beams, posts, footings, and roof framing.
It can help compare ground snow load, flat roof snow load, sloped roof snow load, roof area, rafter PLF, beam PLF, total snow weight, and support reactions.
Your result shows estimated flat roof snow load, sloped roof snow load, adjusted snow load with drift and surcharge, total snow weight, rafter line load, beam line load, beam total load, and support reactions. These are planning estimates only.
Snow load is the weight of snow that a roof or structural member must support. It depends on location, roof shape, exposure, thermal conditions, importance category, and drift conditions.
Ground snow load is the snow load measured or mapped for the ground at a location. Roof snow load is usually calculated from ground snow load using code-based factors.
Multiply snow load in pounds per square foot by the tributary width in feet. For example, 30 PSF over a 10-foot tributary width equals 300 PLF.
No. Final snow load design should follow local building code, local ground snow load maps, drift requirements, unbalanced snow checks, and professional engineering review when required.