Roof Load Calculator
Estimate the total design load on a roof from dead, live, snow, and additional loads. Calculate roof area, total load, and approximate load carried by each rafter or truss.
Enter roof details
Result
Enter your roof dimensions and design loads to see the estimate.
Dead load
The permanent weight of roofing, sheathing, framing, insulation, ceilings, solar panels, and attached equipment.
Live and snow loads
Temporary loads caused by workers, maintenance, stored materials, and accumulated snow or ice.
Roof slope factor
The calculator converts the horizontal footprint into approximate sloped roof surface area using the selected pitch.
Frequently asked questions
What does psf mean?
PSF means pounds per square foot. It describes how much load is applied over each square foot of roof area.
Should dead, live, and snow loads always be added together?
This calculator provides a simple conservative estimate by adding them. Structural codes often use specific load combinations and reduction factors, so final design values may differ.
Does roof pitch affect the load?
Pitch changes the roof surface area. Snow and wind calculations may also use slope-related factors that are not included in this simplified estimate.
Can I use this calculator to size rafters or trusses?
No. Member sizing also depends on species, grade, span, spacing, deflection limits, connections, and code-prescribed load combinations.
Results are estimates generated locally in your browser from standard geometry, material yield and waste assumptions. They are for planning purposes only, not engineering, structural, code or supplier advice. Confirm dimensions, material strength, delivery constraints and local building codes with a licensed professional before purchasing or building. VisionVix accepts no liability for decisions based on this tool's output.
