Roofing Calculator
Estimate roofing squares, square footage, bundles, pitch adjustment, and waste.
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How this calculator works
Estimated roof area = footprint area × √(1 + (pitch/12)²) × (1 + waste). One roofing square = 100 sq ft.
Worked example
A 50 × 30 ft footprint with a 6:12 pitch and 10% waste is roughly 18.45 roofing squares.
Sources & assumptions
A roofing square represents 100 square feet of roof area. The pitch adjustment uses right-triangle geometry, and three bundles per square is only a common planning assumption; product coverage controls the purchase quantity.
Frequently asked questions
What is a roofing square?
A roofing square is 100 square feet of roof area.
Does this replace a roof measurement?
No. Hips, valleys, dormers, overhangs, and complex geometry can materially change the result.
Shingle bundle guide
See roofing-square conversions, product coverage, and 10–15% waste examples in How many bundles of shingles do I need?