Measure footprint and pitch before area
Enter the horizontal roof rectangle or a measured footprint, then the rise per 12. Valleys, hips, dormers and steep cut-up roofs need extra waste or separate sections.
- A 6:12 pitch is a rise, not an angle — do not enter degrees in the rise field.
- Use net panel or roll coverage after laps, not the nominal bundle or roll size.
- Flashings are linear; do not derive them from squares alone.
Geometry, then covering, then accessories
Use roof pitch when you only need the multiplier. Use the main roofing calculator for gable shingles and squares, hip roof when all four sides pitch, snow load only as planning pounds from a stated psf, metal roofing for panels, underlayment for rolls, flashing for linear pieces, ridge cap for hip-and-ridge bundles, waste when you are documenting allowance, and cost only after area exists.
Squares, bundles, rolls and pieces
A square is 100 square feet of coverage. Bundles per square, roll coverage and flashing piece length come from the selected product, not a universal default.
- Starter, ridge, cap, ventilation and drip edge are separate takeoff items.
- Increase waste for valleys, hips, dormers and cut-up roofs; keep the percentage visible.
- Replace any planning rate with a dated supplier figure before quoting.
Planning boundary
These tools estimate coverage. They do not design structure, ventilation, drainage, ice-barrier requirements or a weather-tight specification.