About this calculator

Plan area is converted to true slope area using the pitch. Tile count uses the tile's covering width and gauge (exposed length), so check the manufacturer's datasheet for your exact tile.

Formula: Slope area = plan area ÷ cos(pitch); tiles = area × tiles per m² × (1 + waste)

Frequently asked questions

What does the Roof Tile & Replacement Materials Calculator do?

Count roof tiles, battens, membrane, ridge tiles and fixings for a full re-roof or a partial repair, with waste and an optional cost estimate. Plan area is converted to true slope area using the pitch. Tile count uses the tile's covering width and gauge (exposed length), so check the manufacturer's datasheet for your exact tile.

Is the Roof Tile & Replacement Materials Calculator free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the Roof Tile & Replacement Materials Calculator?

Results are calculated in real time using the formula Slope area = plan area ÷ cos(pitch); tiles = area × tiles per m² × (1 + waste). Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified roofing professional before committing to a purchase or a job.

What inputs does the Roof Tile & Replacement Materials Calculator need?

Enter values for: Roof plan length (m), Roof plan width incl. overhang (m), Roof pitch (degrees), Tile type, Area to replace (%), Waste & breakage (%). Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the Roof Tile & Replacement Materials Calculator on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.