How to tile a shower floor with mosaic tiles

Any tile size and format can be used on a shower floor however the fall or gradient must be considered. This is why using mosaics to tile a shower floor is a popular choice, their smaller size and flexibility makes it easier for them to sit with the fall of the subfloor, rather than larger tiles that would need precise ‘envelope’ cuts to help sit flush.

In this guide we take you through step by step on how to tile a shower floor with mosaic tiles.

When tiling onto a shower floor, it is essential that the fall towards the drainage is incorporated into the substrate, this will aid waterflow and avoid any flooding of the shower area.

Prefabricated shower trays such as the Topps Wet Room Tray or wedi Fundo Primo Shower Kit are the perfect wet room solution as the necessary fall is built in, ready for you to tile over.

As with all tiling installations, it’s important to plan the layout of your tiles before fixing them. Start from where the waste pipe is located and cut the mosaic sheet so it fits around the waste unit. To fit, simply cut through the mesh backing with a utility knife.

Remember to consider the depth of the grate for the waste to ensure it sits below the level of the tiles so water can flow into the waste pipe without obstruction.

Continue laying your mosaic sheets from the waste pipe outwards towards the edges of the shower floor. It’s easiest to cut the sheets as you go rather than once you’ve started fixing. Remember to allow a 3mm expansion gap around the perimeter of the shower floor.

Once you’ve completed your planning and cutting to size, remove all the sheets and prepare the substrate according to the manufacturer’s instructions. You may also need to prime it with a suitable primer.

Using a suitable adhesive (according to the substrate requirements) spread the adhesive directly onto the substrate using a 4-6mm notched trowel. Ensure it’s spread evenly and that the lines formed are all facing in the same direction.

Place the mosaics into their predetermined positions and press firmly down to embed them into the tile adhesive.  Repeat each step in small working areas until you’ve covered the shower floor. Remember to remove any adhesive from the surface of the mosaics with a damp sponge as you go.

When grouting a shower floor, we recommend using BAL Micromax3. Before you grout, test for any potential staining risk by using a few off cuts. If there is any discolouration or it’s difficult to remove it then seal your mosaics using the BAL Protective Sealer.

Mix the grout as per the instructions and then use a grout float to apply the grout to the tile surface and trowel across, working it into the joints. Ensure you don’t grout to the very edges of your mosaics as you’ll need to seal the perimeter using the matching silicone to your grout.

Once applied, allow 10-15 minutes (at 20˚^C) for the grout to be touch dry, using a damp sponge start to clean the surface in a diagonal motion to the grout joints to remove excess grout from the tile surface. Keep rinsing the sponge in clean water and ensure it is only damp each time, too much pressure or water will wash out the pigment from your grout joint.

After around 4 hours, you can wash off the remaining grout haze from the tile surface using the Fila Porcelain Cement Residue Remover. Apply the silicone sealant around the edges of your shower and then leave your shower to fully cure for at least two weeks before using it.

For advice on maintaining your mosaic floor, read our guide on cleaning mosaic tiles.