Roofing Material Calculator

Estimate shingles, roof tiles or metal panels, plus the materials that finish the roof.

Your inputs

Project name (optional)

Roof style

Simple styles assume a rectangular building and equal pitch. Use multiple sections for additions, valleys, dormers or mixed pitches.

Gable: two equal slopes; ridge follows building length

Roofing material

Overlapping shingle courses: use installed bundle coverage

Measurement unitsUS customaryMetric

Building length (ridge direction) (ft)

Building width (across slope) (ft)

Horizontal overhang on every side (in)

Added once to each side of the building footprint. Enter 0 if dimensions already include eaves.

Pitch rise per 12 run

Pitch is rise per 12 horizontal run; slope length is the hypotenuse

Installed shingle coverage per bundle (ft²)

Example: GAF Timberline HDZ, 3 bundles per square. Replace with your product label.

Waste allowance (%)

Planning suggestions: simple gable/shed 10%, hip/complex 15%. Adjust for cuts, breakage and supplier advice. For metal, this adds spare panels after layout.

Accessories, underlayment & cost

Include roof accessories?

Installed underlayment coverage per roll (0 = omit) (ft²)

Enter usable coverage after laps and required layers. 0 omits it; no universal roll coverage is assumed.

Ice / water membrane area (0 = omit) (ft²)

Measured required area, including any required upslope extension. Counted separately from field underlayment.

Include material cost?

Complete the required inputs to calculate. Check material settings for additional fields.

Results

Enter dimensions and check the material settings to calculate.

Use this calculator as a guide. Independently verify all calculations for accuracy before starting your project.

“Measure twice. Cut once”
-- dad