Roofing
Roof Pitch Calculator
Your measurements : vertical rise, horizontal run. Your estimate : angle, slope, rise per 12 run.
How the calculation works
Roof Pitch Calculator
Angle = atan(Vertical rise / Horizontal run) × 180 / π; Slope = 100 × Vertical rise / Horizontal runBefore you order
- A simple roof with one uniform pitch is assumed. Length and width are horizontal plan dimensions; overhang is horizontal on every side. Valleys, hips, dormers and overlaps need separate allowances.
- Planning estimate only. This is not a structural design, a safety approval or a local code check.
Worked example
- Vertical rise
- 2 m
- Horizontal run
- 4 m
Angle 26.57 °
Slope 50 %