In most cases, yes. Microcement can be laid over an existing tiled floor or wall, as long as the tiles are sound and firmly bonded. It's one of the main reasons people choose it: you get a new continuous surface without ripping out what's there.
"Most cases" is doing real work in that sentence, though. Whether a tiled surface is suitable comes down to the condition of the tiles underneath, and that is decided on site, not over the phone.
Why go over tiles at all
Removing tiles is slow, noisy and messy, and the floor underneath usually needs work before anything new goes down. Laying over sound tiles avoids a full demolition, with no screed and far less downtime.
Microcement is a thin system, two to three millimetres thick, so it adds very little height to the floor.
What decides whether your tiles are suitable
The tiles have to be stuck down properly. A tile that has lost its bond to the floor is called drummy, because it sounds hollow when you tap it. Microcement bonds to the tile surface, so if the tile underneath is loose, the finish above it is only as stable as that tile.
So the first job is to sound the floor for drummy tiles. We also note where the building's movement joints are, because those are carried through the new finish and detailed, not covered over.
How it's done
The method below is how we prepared the restaurant floor at Paloma Pizza Bar, and it is the standard approach for a tiled floor:
- Grind back. The whole tiled area is ground back in full.
- Deal with failed tiles. Drummy tiles are removed and the voids filled. Only the failed tiles come out; the sound floor stays.
- Prime. A primer suited to the surface goes down.
- Reinforce. A reinforcing mesh coat goes over the entire floor. This bridges the old grout lines so they don't telegraph through the finish.
- Finish. The coloured microcement coats are troweled on by hand, then sealed.
Grinding tiles makes dust, and that dust can contain silica from the tile and adhesive. The microcement itself contains no crystalline silica, but the preparation is a separate matter, so we control the dust on site with extraction and protective equipment.
A real example: Paloma Pizza Bar
Paloma's Hawthorn restaurant needed a new floor without the time and disruption of lifting the existing tiles. Around 60 m² of microcement was laid over the tiled floor in a custom terracotta colour, following the method above. Drummy tiles were removed and filled, the rest of the floor was kept, and the mesh coat bridged the old grout lines.
The floor was completed in five days, and it now runs as one continuous finish from the dining room to the pizza counter and kitchen pass. See the project.
What it costs
Microcement over tiles is priced the same way as any microcement floor or wall: from $200/m² + GST, with standard preparation included. The condition of the tiles is one of the things that moves the price, which is why we quote after seeing the surface. Our microcement pricing guide covers what else affects it.
The short answer
If your tiles are sound and firmly bonded, microcement can go straight over them with the right preparation, and you avoid a full demolition. If some are loose, those come out and are repaired first. Either way, the decision should be made by someone who has tapped every tile.
Thinking about tiles in your home or venue? Get a quote and we'll come and assess them.