Roof Snow Load Calculator
Create a preliminary roof snow-load estimate from ground load, entered adjustment factors, plan dimensions and roof pitch.
Default project preview
21 psf
Horizontal plan area
1,200 ft²
Sloped roof area
1,341.6 ft²
Total snow weight
25,200 lb
Metric load
1.01 kPa
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Preliminary roof load = ground snow load × exposure × thermal × importance × roof factor. Total weight uses the horizontal plan area, not the sloped surface area.
FAQ
Roof Snow Load Calculator questions
Why is total snow weight based on plan area?+
Roof snow load is commonly expressed on horizontal projection, while the sloped area is reported separately for geometry.
Does this include snow drifting?+
No. Drifts at higher walls, valleys, parapets and roof steps can create much larger local loads.
Can this verify an existing roof is safe?+
No. Existing capacity requires structural evaluation of members, connections, damage and actual loading.