🏠 Roof Pitch Calculator
Calculate roof pitch, angle, and rafter length
How Roof Pitch Calculation Works
Formula
Pitch = Rise/Run × 12; Angle = arctan(Rise/Run)
- 1Enter the rise (vertical height) and run (horizontal distance).
- 2Pitch ratio is calculated as rise per 12 units of run.
- 3The angle in degrees is found using arctan(rise/run).
- 4The grade percentage is (rise/run) × 100.
- 5Rafter length is calculated using the Pythagorean theorem.
About Roof Pitch Calculator
Calculate roof pitch from rise and run. Get results as a ratio (e.g. 6:12), degrees, and percentage grade. Also calculates rafter length.
Frequently Asked Questions
What is a common roof pitch?
The most common roof pitches are between 4:12 and 9:12. A 4:12 pitch is the minimum for standard shingles, while 6:12 is the most popular for residential homes.
What roof pitch is considered steep?
A roof pitch above 9:12 (about 37 degrees) is considered steep. Pitches above 12:12 (45 degrees) require special safety equipment for workers and affect material choices.
How does pitch affect roofing cost?
Steeper roofs cost more due to additional materials, safety requirements, and longer labor time. A steep roof may need 20-30% more shingles than a low-slope roof of the same footprint.