Roofing Calculator (Squares, Bundles & Pitch Factor)
calc_roofingRead-only
Roof area from the house footprint and pitch, converted to roofing squares (100 sq ft) and shingle bundles. Formula: Pitch factor = √(1 + (rise/12)²). Roof area = (L + 2×overhang) × (W + 2×overhang) × pitch factor. Squares = area ÷ 100 × (1 + waste%).
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| waste_pct | No | Waste allowance (%); default 10 | |
| pitch_rise | No | Pitch (rise per 12 in run) (in); default 6 | |
| overhang_in | No | Eave/rake overhang (in); default 12 | |
| bundles_per_square | No | Bundles per square (see wrapper); default 3 | |
| footprint_width_ft | No | Footprint width (ft); default 30 | |
| footprint_length_ft | No | Footprint length (ft); default 40 |