What Is the Roof Pitch Calculator?
Calculate roof pitch ratio, angle in degrees, pitch factor, and rafter length for roof construction planning. While not a stair calculator, roof pitch math uses the same rise-over-run trigonometry and is essential for projects that include roofed stair towers, covered exterior stairs, or porch roofs above deck stairs.
How to Use This Calculator
- Enter the rise (inches per 12 inches of run) or the total rise and run.
- Review the pitch ratio (e.g., 6:12), angle in degrees, and pitch factor.
- Use the pitch factor to calculate rafter length from the horizontal run.
Why Accurate Roof Pitch Calculations Matter
Roof pitch determines material selection (shingles require minimum 2:12 pitch), snow load capacity, and attic usability. For stair projects, the porch or tower roof pitch affects headroom at the top of exterior stairs.
Building Code References
Related Tools
Frequently Asked Questions
What does a 6:12 roof pitch mean?+
A 6:12 pitch means the roof rises 6 inches vertically for every 12 inches of horizontal run. This equals approximately 26.6 degrees and is one of the most common residential roof pitches.