Free tool
Roof pitch calculator
Enter rise and run to get pitch, slope factor, angle, and slope-adjusted roof area.
Roof
Footprint = the flat area the roof covers (building outline). Slope factor scales it to the actual roof surface.
Results
- Pitch
- 6/12
- Slope factor
- 1.118
- Angle
- 26.6°
- Roof area (sloped)
- 2,236 SF
- With waste
- 2,460 SF
- Squares
- 24.6
Estimate — verify against actual roof measurements before ordering.
Frequently asked
- What is roof pitch?
- Roof pitch is the vertical rise over a 12-inch horizontal run — a 6/12 pitch rises 6 inches for every 12 inches of run.
- How do you find roof area from the footprint?
- Multiply the building footprint area by the slope factor (√(rise² + run²) / run). This calculator does it and adds waste.
- What is a slope factor?
- A multiplier that converts flat footprint area to the true sloped roof surface. A 6/12 roof has a slope factor of about 1.118.
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