Roofing Calculator – Squares and Materials

Calculate roofing squares needed and shingles for any roof.

About This Calculator

Calculate roofing squares needed and shingles for any roof. Use the calculator above for instant results.

Worked Examples

Example 1: 40x25ft, 2-side gable roof

  • Area: 2,000 sq ft + 15% waste = 2,300 sq ft
  • = 23 squares | 69 bundles

Answer: 23 squares / 69 bundles

Example 2: 30x20ft simple roof

  • Area: 600 sq ft + 15% = 690 sq ft = 6.9 squares

Answer: 7 squares

Example 3: Complex roof 4 sides

  • 40x25ft x 4 sides: 16 squares + waste: 18.4 squares

Answer: 18.4 squares

Who Uses This Calculator?

🏗️
Roofers

Estimate shingles for any job.

🏠
Homeowners

Understand roofing material quantities.

💼
Contractors

Bid roofing projects accurately.

📏
DIYers

Plan roof repair or replacement.

Common Mistakes to Avoid

❌ Forgetting roof pitch factor

A steeper roof covers more actual surface area than its footprint suggests. For steep roofs (>6/12 pitch), add 10-20% more.

❌ Buying exact squares

Always buy 10-15% extra for cuts, waste, ridges, and potential future repairs.

Frequently Asked Questions

What is a roofing square?

100 square feet of roofing. The standard unit for estimating roofing materials.

How many bundles per square?

3 bundles per square for standard 3-tab shingles. Architectural shingles: also ~3 bundles but verify.

Roof lifespan by material?

Asphalt shingles: 20-30 years. Metal: 40-70 years. Tile: 50-100 years. Slate: 75-150 years.