Roofing Calculator
Estimate shingles using squares and bundles. Adjust waste and bundle coverage.
Quick guide
- Start with roof area, then add waste for valleys/hips and cut shingles.
- Convert to squares (100 sq ft) and then to bundles.
- Round up—running short mid-roof is expensive.
Roofing Calculator
Estimate shingles using squares and bundles. Adjust waste and bundle coverage.
Units
Results
- Estimated squares (100 sq ft each)
- 22
- Estimated bundles
- 67
How to measure roof area
- Measure each roof plane (length × slope length), then add them.
- Include dormers and overhangs if they will be shingled.
- Use a higher waste factor for complex roofs (valleys, hips, dormers).
Assumptions to double-check
- Bundles per square vary by shingle type—confirm with the product label.
- Starter, ridge caps, and underlayment are separate material needs.
- Roof pitch affects true surface area vs footprint area.
Buying tips
- Confirm bundles per square and ridge cap coverage for your shingle.
- Order extra for cuts and future repairs (same color/batch if possible).
- Consider delivery placement and weather windows before ordering.
Last updated: Dec 2025
FAQ
What is a roofing square?
A roofing square is 100 square feet of roof area.
How many bundles are in a square?
Often 3 bundles per square, but it depends on product and exposure. Use the label when possible.
Why add waste?
Cuts, valleys, hips and mistakes require extra shingles.
Related
In Roofing & exterior
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Results are estimates for informational purposes only. Always verify measurements and product specifications.