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Shingle Calculator
Estimate asphalt shingle bundles for any roof. Includes pitch correction, waste, underlayment rolls, nails, starter course, and ridge cap.
Roof and shingle details
Shingles you need
45 bundles
Covers 14.76 squares of roof.
- Footprint
- 1,200 sq ft
- Pitch multiplier
- 1.118 (6/12)
- Roof area
- 1,342 sq ft
- With waste
- 1,476 sq ft
- Squares
- 14.76
- Underlayment rolls
- 4
- Nails (lb)
- 30
- Starter course
- 80 ft
- Ridge cap shingles
- 40
Frequently Asked Questions about the Shingle Calculator
How many bundles of shingles do I need per square?
Most 3-tab and architectural asphalt shingles take 3 bundles to cover one roofing square (100 sq ft). Heavyweight designer shingles cover less per bundle and usually take 4 bundles per square.
How does roof pitch change how many shingles I need?
A pitched roof has more surface area than its footprint. The calculator multiplies your footprint by sqrt(1 + (rise/run)^2) to get true sloped area. A 6/12 pitch gives about 1.118; a 12/12 about 1.414.
How much waste should I add for shingles?
Use 10% for a simple gable roof with straight runs. Go to 15% for hip roofs with more cut shingles at the seams, and 15-20% for roofs with dormers, valleys, skylights, or unusual angles.
Should I enter footprint or actual roof area?
Enter the footprint (the building outline from above) and let the calculator apply the pitch multiplier. Pick custom area only if you have already measured the sloped roof surface directly.
What else do I need besides shingles?
A typical asphalt shingle job also needs underlayment (about 1 roll per 400 sq ft), roofing nails (about 2 lb per square), starter strip along every eave, and ridge cap shingles along every ridge.