đ Roof Area Calculator
Calculate total roof area from building dimensions and pitch. Get results in square feet and roofing squares for any roof type.
How to Use This Calculator
Enter your building footprint dimensions (length and width). Select your roof pitch from the dropdown â if unsure, 6/12 is the most common residential pitch. Choose your roof type (gable, hip, shed, flat, or gambrel). Results update instantly as you change any input.
Understanding Your Results
Total roof area accounts for the slope of your roof â steeper pitches create more surface area over the same footprint. Roofing squares (1 square = 100 sq ft) are the standard unit for ordering materials and getting contractor quotes. The pitch multiplier shows how much extra area the slope adds compared to a flat projection.
Frequently Asked Questions
How do I calculate roof area?
Multiply the building footprint area by the pitch multiplier for your roof slope. For a gable roof, the footprint is length à width. The pitch multiplier increases with steeper slopes â a 6/12 pitch has a multiplier of 1.118, meaning 11.8% more area than the footprint.
What is a roofing square?
A roofing square is 100 square feet of roof area. Roofing materials are commonly sold and priced per square. To convert square feet to squares, divide by 100.
How does roof pitch affect area?
Steeper pitches create more roof surface area over the same footprint. A flat roof (0/12) has no extra area, while a 12/12 pitch (45°) adds about 41% more area than the footprint.
What is the difference between gable and hip roof area?
A hip roof has slopes on all four sides, creating slightly more total area than a gable roof with the same footprint and pitch. Hip roofs typically have about 5-10% more area than equivalent gable roofs.