Roofing Calculator
Estimate sloped roof area and roofing squares from plan dimensions, pitch and waste allowance.
Results
Roof surface area
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Area including waste
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Roofing squares
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Use the result as a planning estimate and verify project-specific dimensions, product information and local requirements where relevant.
How it works
The calculator multiplies horizontal plan area by the slope factor derived from rise and run.
roof area = plan area × √(1 + (rise ÷ 12)²)Limitations
- Assumes a roof where the entered horizontal plan area represents the complete roof footprint; hips, valleys, overhangs and complex geometry require separate sections.