Every roof shape has unique geometry that affects area, material quantities, and cost. Choose your roof type below for a shape-specific calculator with accurate formulas.
Each calculator uses the exact geometry of that roof shape to compute accurate area, slope lengths, and material estimates.
The most common residential roof. Two rectangular slopes meeting at a ridge. Simple, cost-effective, and excellent for drainage.
Calculate Gable RoofAll four sides slope downward from the ridge. More stable in wind, more complex to build. Two trapezoidal + two triangular sides.
Calculate Hip RoofBarn-style roof with two slopes on each side — steep lower and shallow upper. Maximizes attic/loft space.
Calculate Gambrel RoofFour-sided gambrel with steep walls on all sides and a flat or low-slope top. Creates maximum usable upper-floor space.
Calculate Mansard RoofLevel or nearly-level roof common in commercial and modern residential. Uses membrane materials (TPO, EPDM, modified bitumen).
Calculate Flat RoofSingle sloping surface, also called a skillion or lean-to. Popular for additions, porches, and modern architecture.
Calculate Shed RoofAsymmetrical gable with a short front slope and long back slope. Classic New England colonial style with unique character.
Calculate Saltbox Roof| Shape | Complexity | Cost Factor | Wind Resistance | Attic Space | Best For |
|---|---|---|---|---|---|
| Gable | Simple | 1.0× (baseline) | Moderate | Good | Most homes |
| Hip | Moderate | 1.15–1.25× | Excellent | Limited | Hurricane zones |
| Gambrel | Moderate | 1.1–1.2× | Poor | Excellent | Barns, colonial |
| Mansard | Complex | 1.3–1.5× | Poor | Maximum | Urban, multi-story |
| Flat | Simple | 0.9–1.0× | Good | None | Commercial, modern |
| Shed | Simplest | 0.85–0.95× | Moderate | None | Additions, porches |
| Saltbox | Moderate | 1.05–1.15× | Good | Moderate | Colonial style |
Once you've calculated your roof area, use our cost calculator to get an instant replacement estimate.