Many renovation projects involve ripping out tiled floors and walls. This can be a cumbersome process – the noise, the dust, and the hassle of disposing the tiles are enough to put many off. The good news is that, with the right kind of tile, you can simply tile over your existing tiles.
So, how to go about tiling over tiles? Even with suitable tiles, such as ultra-thin porcelain, you’ll need to prepare the right foundation. Simply follow these seven steps to achieve the perfect over-tiled look.
Check the strength of your walls and floors
This first step is without doubt the most important. A building’s substrate (aka “wall/floor construction”) can only take a certain amount of weight, depending on the materials used. Therefore, if your existing floor is covered with very thick tiles or large slabs of stone, over-tiling may not be an option. If in doubt, you should seek professional advice before laying tiles on top of existing tiles.
The calculation is fairly simple. First, determine what material your wall is made from. Then calculate the weight per square metre of the existing tiles and the tiles you want to add. Lastly, check that the total weight is below the maximum recommended loading for the wall type. Here’s a handy table to help you:
The lighter your new tiles, the easier it is to meet the requirements. Porcel-Thin tiles boast a remarkably low weight per square metre ratio, making them perfect for over-tiling. You can check the weights per tile and per square metre for every single tile product in our range.
Ensure the surface is completely flat
The wall or floor you are over-tiling must be flat, uniform, and free of high points. Use a straight edge to ensure the area is uniformly flat– remove small high points with a grinder or remove feature tile completely. If the existing tiles are heavily riven or textured it may not be possible to over tile and the tiles will need to be removed.
Check the substrate is sound
This is where a professional eye makes all the difference. If you tile over an unsound substrate, the result may be an unstable surface that causes tiles to fail. Loose or cracked tiles and grout need to be repaired first– if one or two tiles are loose, simply replace or refit them. However, any more than this probably means there are deeper issues with the substrate. You’ll need to remove the old tiles for further investigation – best left to the experts
Before tiling, make sure the entire surface is squeaky clean. We recommend cleaning with a mild acid solution, such as diluted brick cleaner. Don’t forget to cover your hands and eyes as a precaution and to follow the manufacturer’s instructions. Ensure that all grease, dust and dirt is thoroughly removed before rinsing down the surface with cold water. Leave to dry for at least 24 hours before moving on to Step 5…
Prepare the surface with a tile over tile primer
The existing surface to be over-tiled must be correctly “primed” before over-laying. This means using a proper tile over tile primer – mixing PVA with sand is NOT suitable. Quality products such as Tilemaster Prime + Grip provide an excellent bonding surface for adhesives (Step 6.) Whichever professional primer you choose, make sure to follow the manufacturer’s guidance carefully.
Use the correct adhesive
The correct adhesive will depend on the kind of area you are over-tiling. For wet and humid areas, such as bathrooms and wetrooms, we suggest using a high-performance adhesive such as Tilemaster Ultimate. For regular surfaces, a standard Setaflex adhesive is perfectly suitable. For the best results, try to use a primer and adhesive from the same brand.
Finish off with grouting
Once the tile adhesive has fully set, it’s time to grout. Make sure your tile grout is of a good quality – don’t cut any corners at this late stage.
Good news: you’re now ready to lay some tiles! To find inspiration for your next over-tiling project, explore our vast collection of ultra-thin porcelain tiles. If you have any questions about tiling over a tiled floor, feel free to contact us.