Roofing, Insulation & Exterior calculator
Roof Tile Calculator
Estimate roof tile coverage and quantity from horizontal footprint area, pitch, waste and effective product coverage.
Estimate roof tile coverage and quantity from horizontal footprint area, pitch, waste and effective product coverage. Use finished project dimensions and product-specific data where available rather than generic defaults. The most sensitive assumption here is installed gauge and headlap. Roof-tile coverage depends on the installed gauge and overlap, not simply the tile's face dimensions. Use the manufacturer's installed coverage.
What you need to enter
The Roof Tile Calculator uses the following project information to calculate the result.
- Building footprint area
- Roof pitch
- Waste (%)
- Coverage per pack/unit
Calculator result
Adjusted roof area and optional packs/units
How the Roof Tile Calculator works
Core method: footprint adjusted for pitch, waste and unit coverage. On the Roof Tile Calculator, this relationship is applied specifically to roof tile quantity from sloping area and product coverage. Compatible measurements are converted to a common internal unit before calculation, then the result is returned in the selected unit system. The main variable to verify is installed gauge and headlap.
Roof Tile Calculator worked example
Roof Tile Calculator example: For a 100 m² horizontal roof footprint at 30°, dividing by cos(30°) gives about 115.5 m² of simple sloping area. A 10% allowance brings that to roughly 127 m² before product-specific laps and detailing for roof tile quantity from sloping area and product coverage. Before relying on that figure, check installed gauge and headlap; the final decision should also follow the actual product or project specification.
Important calculation assumptions
For roof tile quantity from sloping area and product coverage, roof-tile coverage depends on the installed gauge and overlap, not simply the tile's face dimensions. Use the manufacturer's installed coverage.
Frequently asked questions
What should I check on site before using the Roof Tile Calculator?
For roof tile quantity from sloping area and product coverage, use horizontal footprint area and true roof pitch, then enter waste and the effective coverage of the chosen roof product. This keeps the calculation tied to the actual job rather than a generic assumption.
What can cause installed gauge and headlap to differ from my first estimate in the Roof Tile Calculator?
In the Roof Tile Calculator, errors in installed gauge and headlap can materially affect the result. Roof-tile coverage depends on the installed gauge and overlap, not simply the tile's face dimensions. Use the manufacturer's installed coverage.
What roof details should I add after using the Roof Tile Calculator?
Convert the Roof Tile Calculator's adjusted roof area using the exact tile's gauge and coverage, not a generic pack rate. Ridge, hip, verge, valley and ventilation tiles are separate take-off items and should be counted from the roof geometry.