Roof Angle Calculator

Calculate the roof angle in degrees and radians from rise and run measurements.

Formula & Explanation

The roof angle is calculated using the arctangent (inverse tangent) function: Angle (degrees) = arctan(Rise ÷ Run) × (180 ÷ π) Angle (radians) = arctan(Rise ÷ Run) For a 6:12 roof (6 feet rise over 12 feet run), the angle is arctan(6÷12) = arctan(0.5) = 26.57 degrees or 0.464 radians. This calculation converts pitch measurements into angle format, which is useful for structural engineering calculations and compatibility with certain roofing materials.

Assumptions

  • Rise and run are measured in the same units
  • Angle is measured from horizontal (0° = flat, 90° = vertical)
  • For residential roofing, typical angles range from 18° to 45°

Example Calculation

A 6:12 pitch has an angle of approximately 26.57 degrees or 0.4636 radians from horizontal.

Inputs

rise:6
run:12

Results

angle:26.57
angleRadians:0.4636

Common Pitch Angles

pitchangle
3:1214.04°
4:1218.43°
5:1222.62°
6:1226.57°
8:1233.69°
12:1245.00°

Frequently Asked Questions

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