Roofing Calculators

Roofing material estimates require accounting for roof pitch — the steeper the roof, the more material you need. A 6/12 pitch adds 12% more surface area than a flat measurement, while a 12/12 pitch adds 41%. Our calculators apply the correct pitch multiplier automatically.

Whether you're replacing asphalt shingles, installing metal panels, or sizing gutters for proper drainage, these tools give you estimated quantities for ordering materials and getting contractor bids.

All Roofing Tools

Roofing Quick Reference

• 1 square = 100 square feet of roof area
• 3 bundles = 1 square (for standard 3-tab and architectural shingles)
• Pitch multiplier = sqrt(1 + (rise/12)²) — applied to flat footprint area
• Ridge cap: 1 bundle covers ~35 linear feet
• Waste factor: 10% for simple gable, 15-20% for complex hip/valley roofs

Disclaimer

These calculators provide estimates only. Actual material requirements vary based on roof complexity, waste from cuts, and manufacturer specifications. Always verify quantities with your supplier or roofing contractor before ordering. See our Terms of Use.