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Free construction planning tool
Roof Pitch Area Calculator
Convert horizontal projected roof area to sloped roof surface area using rise per 12 inches of run.
How this calculator works
Projected roof area (sq ft) × √[1 + (rise in inches ÷ 12)²] × (1 + waste % ÷ 100).
Use actual horizontal roof area, not floor area unless overhangs and footprint match. Add dormers, separate roof planes, valleys and material-specific waste; the third field adds separately measured sloped area.
Use field-verified dimensions. This planning estimate does not substitute for a complete takeoff, structural design or local supplier quote.
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