Calculate roof pitch and roof angle from rise and run measurements.
Roof pitch is commonly shown as rise over 12 inches of run. A 6-inch rise over 12 inches of run is a 6/12 pitch.
Formula: pitch = rise ÷ run
| 4/12 | About 18.43° |
| 6/12 | About 26.57° |
| 8/12 | About 33.69° |
Roof pitch is the rise of the roof compared to its horizontal run, commonly shown as inches of rise per 12 inches of run.
Divide rise by run, then use arctangent to calculate the angle.
A 6/12 pitch means the roof rises 6 inches for every 12 inches of horizontal run.