Use the same unit for rise and run. Enter only those two values for pitch, percentage, angle and slope factor. Add span for rafter length; add roof length for both gable slopes; add bundle coverage and price only when you need a material estimate.
Pitch, percent and factor: Vertical rise ÷ Horizontal run × 12 · % = Vertical rise ÷ Horizontal run × 100
Rise and run calculate slope without roof dimensions. Optional area estimates model a symmetrical gable roof and exclude overhangs, dormers, valleys and ridge materials. Confirm structural dimensions with a qualified professional.