Roof Calculator | Shingles, Squares & Roofing Materials
Calculate roofing squares, shingles, bundles, felt underlayment, ridge cap, and starter strips for any roof shape. Enter footprint dimensions and pitch to get complete material quantities with a configurable waste factor for hips, valleys, and cuts.
Roof Shape
Shingle Type
Understanding Roofing Squares
Roofing materials are sold by the "square" — one roofing square covers 100 square feet. To find squares needed, divide total roof area (already accounting for pitch) by 100. A 2,000 sq ft footprint with a 6/12 pitch requires about 2,240 sq ft of actual roof surface, or 23 squares.
Roof Pitch Factor Table
| Pitch (rise/run) | Pitch Factor | Description |
|---|---|---|
| 2/12 | 1.02 | Low pitch — nearly flat |
| 4/12 | 1.05 | Low pitch — common on shallow roofs |
| 6/12 | 1.12 | Medium pitch — most residential |
| 8/12 | 1.20 | Medium-steep |
| 10/12 | 1.30 | Steep |
| 12/12 | 1.41 | Very steep — 45° angle |
Shingles vs Other Materials
Asphalt shingles (3-tab or architectural) are the most common roofing material in North America, lasting 20–30 years. Metal roofing lasts 40–70 years but costs 2–3× more. Wood shake has superior aesthetics but requires more maintenance and may not meet fire codes in some regions.
You Might Also Like
Explore 360+ Free Calculators
From math and science to finance and everyday life — all free, no account needed.