Calculate how many roof tiles you need, based on roof area, tiles per m² and recommended waste.
The calculator multiplies the area by the number of tiles per m², and adds waste:
For a roof of 120 m² with 10 tiles per m² and 5% waste, that's 120 × 10 × 1.05 = 1,260 roof tiles.
It varies by product and tile type. Concrete roof tiles are often around 10 tiles per m², while clay roof tiles often need 12–15 tiles per m² due to their smaller size.
The size of the individual tile, the overlap between tiles, and the roof pitch all affect how many tiles are needed per square meter. Always check the manufacturer's data sheet for the exact figure.
Yes, it's wise to account for some waste for cutting at ridges, edges and penetrations, as well as possible breakage during transport and installation. 5% is a common starting point for simple roofs.