Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
Construction
Concrete Volume Calculator
Estimate how many cubic metres of concrete to order for a rectangular slab, footing, or path. Multiply length × width × depth for the in-place volume — add a 5–10% waste allowance before placing the order.
Fill in the required fields to see your result.
Construction
Roof Area Calculator
Calculate the true sloped surface area of a roof from its footprint dimensions and pitch angle. The slope multiplier (1/cos(pitch)) corrects for the fact that a pitched roof has more material area than the horizontal footprint it covers.
Fill in the required fields to see your result.
Key differences
| Concrete Volume Calculator | Roof Area Calculator | |
|---|---|---|
| Category | Construction | Construction |
| Inputs required | 3 | 3 |
| Result | Concrete Volume Needed (m³) | Roof Surface Area (m²) |
| What it does | Estimate how many cubic metres of concrete to order for a rectangular slab, footing, or path. Multiply length × width × depth for the in-place volume — add a 5–10% waste allowance before placing the order. | Calculate the true sloped surface area of a roof from its footprint dimensions and pitch angle. The slope multiplier (1/cos(pitch)) corrects for the fact that a pitched roof has more material area than the horizontal footprint it covers. |