Convert rise and run into pitch notation, equivalent angle, and slope factor.
Use this calculator when you have a roof's rise and run and want the common pitch notation, the matching angle, and a slope factor. It is a measurement check that can feed an early surface-area estimate.
Pitch12 equals rise divided by run multiplied by 12. Angle uses arctangent of rise divided by run. Slope factor is the square root of 1 plus the squared rise-to-run ratio.
A 6 inch rise over a 12 inch run is a 6:12 pitch, about 26.565 degrees, with a slope factor of approximately 1.118034.
Use the result to check a measurement or supply a slope factor to another planning calculator. Verify unusual or inaccessible roofs with a qualified professional.
Different roof planes can have different pitches. Dormers, valleys, hips, overhangs, measurement position, and roof access can affect the full roof estimate.
Pitch alone does not describe the whole roof. It cannot account for multiple planes, dormers, valleys, hips, or safe access conditions.
Yes. Use matching units so the ratio represents the actual slope.
It means the roof rises 6 units for every 12 matching units of horizontal run.
No. Pitch gives a slope relationship. The full area still needs the roof planes, footprint or surface measurements, and geometry.
Short, practical help for the next step in this project.