Roofing Material Calculator

How does roof pitch affect area?

Roof materials are sloped, which means the true surface area is longer than the flat square footage measured from above. The pitch determines the precise multiplier. A steeper pitch yields a larger surface area over the same home base footprint than a shallow pitch.

What is a Roofing Square?

In North America, roofing materials are commonly measured in squares. One square is exactly equal to 100 square feet of surface area.

A single bundle of standard 3-tab or architectural shingles typically covers 33.3 square feet, which means it takes 3 bundles to make one square. Our calculator automatically applies an industry-recommended 10% waste buffer to the bundles to handle cut valleys, rake edges, and hip and ridge gaps.