Roof Area Calculator

Estimate your roof area for replacement, repair, or solar panel planning. Enter your building dimensions and roof details below.

Calculation MethodFrom House FootprintFrom Roof Dimensions

Building Length (ft)

Building Width (ft)

Roof PitchFlat (0-1/12)Low (2/12)Low (3/12)Medium (4/12)Medium (5/12)Medium (6/12)Steep (7/12)Steep (8/12)Very Steep (10/12)Very Steep (12/12)

Steeper roofs have more surface area

Waste Factor10% (Simple roof, few obstacles)15% (Standard — Recommended)20% (Complex roof, many valleys)25% (Very complex, many dormers)

Calculate Roof Area

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Our roofing experts will inspect your roof and provide an accurate quote including materials and labor.

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This calculator provides estimates based on simplified measurements. Actual roof area may vary due to dormers, valleys, chimneys, and other features. A professional inspection is recommended for accurate quotes.