Roofing Material Calculator
Calculate roof squares, shingle bundles, and underlayment needed for your roofing project. Includes pitch adjustment, waste factor, and cost estimates.
Enter Roof Dimensions
Measure from eave to ridge
Total width of the roof section
Rise over run (e.g., 4/12 = 4" rise per 12" run)
Simple roofs: 10% | Complex roofs: 15-20%
Cost Estimates (Optional)
Architectural shingles: $300-500 per square
Average: $200-400 per square (tear-off + install)
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Enter Your Roof Dimensions
Fill in the length, width, and pitch on the left to calculate your roofing needs.
How to Use This Calculator
Formula Explained
The calculator uses the industry-standard roofing formula:
Squares = (Length × Width × Pitch Multiplier) / 100
- • Length and Width are measured in feet
- • Pitch Multiplier accounts for roof slope (steeper = more surface area)
- • Divide by 100 to convert square feet to squares (1 square = 100 sq ft)
- • Add waste factor (10-20%) for cuts, mistakes, and complex features
- • 3 bundles of shingles cover 1 square (standard architectural shingles)
Understanding Roof Pitch
Low Slope (3/12 - 4/12)Walkable, easy to work on
Medium Slope (5/12 - 8/12)Most common for homes
Steep Slope (9/12 - 12/12)Requires safety equipment
Waste Factor Guidelines
Simple Gable Roof10% waste
Hip Roof with Valleys15% waste
Complex Multi-Level Roof20% waste