Roofing Calculator
Estimate roofing area and common shingle purchase quantities from building footprint, roof pitch and waste.
Project details
Estimate
Roof area incl. waste—
Roofing squares—
Bundles to buy—
Planning estimate only. Confirm product dimensions, package coverage and project requirements before purchasing.
How roofing quantity is estimated
For a simple gable roof, footprint area is adjusted by a slope factor based on roof pitch. Waste is then added and the result is converted to roofing squares.
roof area = footprint area × slope factor × (1 + waste %)
What is a roofing square?
One roofing square equals 100 square feet of roof surface. Bundle counts vary by product, so bundles per square is editable.
Roofing Calculator FAQ
Does this work for hips, valleys or dormers?
Use it only as a rough starting point. Complex roof geometry should be measured by individual roof planes.
Why is pitch needed?
A sloped roof has more surface area than its horizontal footprint.
How much waste should I add?
Waste depends on roof complexity, cuts and product.