Can different tile sizes be combined in a floor build-up?

Different tile sizes can be combined in a floor with more than one layer. Surface tiles and functional tiles are designed to be used together in this way, rather than stacked with their joints aligned.

Allowing for joints, each surface tile occupies 44.6 × 44.6 cm or 97.1 × 97.1 cm. Functional tiles, by contrast, come in 52 × 52 cm or 104 × 104 cm sizes and are laid with butt joints, without interlocking edges. Their nominal dimensions are therefore also the dimensions used to calculate coverage.

The layers are laid to different grids so that their joints are offset as intended. Joints in the upper and lower layers never align to form a continuous joint through the floor.

The number of tiles must therefore be calculated separately for each layer. The floor area to be covered is the same for both, but the number of tiles required depends on the coverage dimensions of each tile type.