3-tab shingles: 3 bundles/square. Architectural/dimensional: 3-4 bundles/square (check package). One square = 100 sq ft of roof area. Always order 10% extra for waste and starter course.
3/12: 1.031 • 4/12: 1.054 • 5/12: 1.083 • 6/12: 1.118 • 7/12: 1.158 • 8/12: 1.202 • 10/12: 1.302 • 12/12: 1.414. Multiply footprint area by this factor.
Use this free shingles calculator to get instant, accurate results for your construction project. Simply enter your measurements above and the calculator will automatically compute the result using industry-standard formulas.
Pro Tip: Always add 10-15% extra material to account for waste, cuts, and job-site conditions. This is standard practice recommended by experienced contractors.
| Pitch | Multiplier | Extra % |
|---|---|---|
| 3/12 | ×1.031 | +3.1% |
| 4/12 | ×1.054 | +5.4% |
| 6/12 | ×1.118 | +11.8% |
| 8/12 | ×1.202 | +20.2% |
| 12/12 | ×1.414 | +41.4% |