Carpentry Calcs / Carpentry Calculator Guides NOTES FROM THE WORKBENCH Carpentry Calculator Guides Practical illustrated guides to measuring roof pitch and telling horizontal run from rafter length. Use the examples with our free calculators.
FROM MEASUREMENT TO RESULT Start with the measurement. 01 Measure roof pitch with a level and tape, identify vertical rise and horizontal run, and convert imperial or metric readings into pitch and degrees.
02 See the difference between horizontal roof run, vertical rise and sloped rafter length, with a labeled diagram and an imperial and metric example.
Looking for numbers? Open the printable pitch chart ↗ Use the guide with your measurements
These carpentry calculator guides explain where to measure before entering a value. Start with the field guide that matches your question, then carry the measurements into the related tool.
For a number you already know, use the roof pitch calculator or rafter calculator directly. For a quick conversion, the roof pitch chart compares degrees, percent and rafter factors and includes a printable table.
Each guide states its assumptions and includes a worked example. If a measurement label or result is unclear, send a correction .