Roofing Calculator: How to Estimate Your Roof Replacement

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Ready to estimate roofing? Use our [Roofing Calculator](/roofing-calculator) for professional results.

Roofing is measured in "squares" – one square equals 100 square feet. Let's break it down.

Understanding Roofing Terminology

Roofing Square

1 square = 100 sq ft

This is the standard unit for roofing materials.

Bundles

Typically 3 bundles = 1 square

Pitch

Roof pitch is expressed as a ratio (e.g., 4:12 means 4 inches of rise per 12 inches of run).

How to Calculate Your Roof

Step 1: Measure Each Plane

Length × Width = Area of each plane

Step 2: Add Them Up

Total Square Footage = Sum of all planes

Step 3: Convert to Squares

Squares = Total Square Footage ÷ 100

Step 4: Add Waste

Add 10-15% for waste, especially on complex roofs.

Pro tip: Our [Roofing Calculator](/roofing-calculator) handles all these calculations for you automatically.

Common Roofing Materials

Asphalt Shingles

- Most popular

- $3-$7 per sq ft installed

- 20-30 year lifespan

Metal Roofing

- $8-$20 per sq ft

- 50+ year lifespan

- Energy efficient

Tile Roofing

- $10-$25 per sq ft

- Very durable

- Heavy, needs strong structure

Conclusion

Use our [Roofing Calculator](/roofing-calculator) to estimate materials for your roof project!