Estimated result
Enter measurements and select Calculate.
Simple gable formula
Slope factor = √(1 + (rise ÷ run)²). Base sloped area = building length × span × slope factor. Roofing squares equal adjusted square feet ÷ 100.
Roof boundaries
This model is for one simple symmetrical gable roof. It does not include eaves, dormers, valleys, hips, penetrations, underlayment, bundle coverage, structural load, or code compliance unless separately measured.
Worked example
A 40 ft by 24 ft simple gable footprint with a 6-in-12 pitch uses a slope factor of √1.25 before the editable allowance is applied.
Estimate boundaries
Results use only your entered measurements and assumptions. No supplier, product, price, contractor, building-code, or geolocation API is contacted.