Roofing Calculator
Estimate roofing materials and squares for a roof.
How It Works
Squares = Roof area ÷ 100 × (1 + Waste ÷ 100). Bundles = Squares × 3.
Example
For a 1,000 sq ft roof with 10% waste: (1000 ÷ 100) × 1.1 = 11 squares → 33 bundles.
Frequently Asked Questions
What is a roofing square?
A square is a roofing unit equal to 100 sq ft. Materials and pricing are quoted per square.
How many bundles per square?
Standard 3-tab and architectural shingles pack 3 bundles per square. Heavier shingles may be 4.
What waste factor should I use?
10% is typical; use more for complex roofs with valleys, hips, and penetrations.