How to replace floor tiles

Video by Tommy's Trade Secrets. This walk-through is based on the video "Tommy's Trade Secrets - How to Replace Floor Tiles" from Tommy's Trade Secrets, who goes through how to dig out floor tiles and replace them cleanly. The section on protecting adjacent tiles with tape before you start chiselling is particularly worth paying attention to.

1. Source a matching replacement tile before you start

This sounds obvious, but it catches people out more than almost anything else on this job. If you cannot find a matching tile first, there is no point lifting the broken one — you will just have a gap in the floor instead of a crack. Check whether you have any leftover tiles from when the floor was laid. If not, take a photograph and a piece of grout rubbing to a tile shop. Even then, a perfect match is not always possible if the floor is more than a few years old.

It is worth buying at least two replacement tiles rather than one, in case one cracks during installation. Floor tiles take quite a bit of force to cut, and ceramic in particular has a habit of snapping at an awkward moment.

2. Score and cut the grout joints around the tile

Before anything else, score through the grout around the perimeter of the damaged tile using a grout rake or an oscillating multi-tool. Do not skip this step. If you try to lever up a tile without first cutting the grout, the bond between the grout and the adjacent tiles will pull them up or crack them. Work all the way round, cutting cleanly down to the bed.

Protect the surrounding tiles with masking tape along their edges — it will not stop a really heavy blow, but it gives the chisel blade something to glance off rather than skidding across the face of the tile next door. A decent Stanley knife and a metal straightedge can help score the grout line more precisely before you rake it out fully.

3. Break up the damaged tile and lift the pieces

Drill a hole through the centre of the tile first using a tile or masonry bit — this releases some of the stress and gives your chisel somewhere to start. Then use a cold chisel and club hammer to work outwards from the centre, breaking the tile into manageable pieces. Always work from the middle towards the edges, never the other way round.

Take your time as you approach the joints. The closer you get to the edge, the more careful you need to be. If a large fragment is still bonded to the floor firmly, try angling the chisel under it and twisting gently rather than smashing it. Wear eye protection throughout — fragments of ceramic can travel a surprising distance.

4. Clean back the sub-floor and prepare the bed

Once the tile is out, use the chisel to scrape away all the old adhesive and grout from the sub-floor. You want a flat, clean surface to lay the new tile onto. Any lumps or ridges of old adhesive left behind will show up as high spots under the new tile and may cause it to crack again under foot traffic.

Check the level of the existing floor around the gap. The replacement tile needs to finish at the same height as its neighbours. If there is a lot of old adhesive to remove and you find it difficult to get the level right, a flexible floor tile adhesive with a notched trowel gives you a little room to adjust before it sets.

5. Bed the new tile and allow it to set

Apply floor tile adhesive to the back of the replacement tile using a notched trowel — this is called back-buttering and ensures full coverage without air pockets. Press the tile firmly into position and use a rubber mallet to tap it down flush with the surrounding tiles. Use tile spacers around the edges to keep the grout gaps consistent with the rest of the floor.

Check it is level by laying a spirit level across it and the adjacent tiles in both directions. Make small adjustments while the adhesive is still workable. Then leave it alone. Most floor tile adhesives need at least 24 hours before you can walk on the tile, and some say 48 hours before grouting. Do not rush this — a tile that shifts while the adhesive is curing will sit proud or at an angle.

6. Grout the joints and finish off

Mix the grout to a smooth paste and press it firmly into the joints using a rubber grout float, working at a 45-degree angle across the gap. Pack the joints fully — any voids will let water get under the tile over time, which is how tiles end up cracking again in the first place. Wipe off the excess from the tile face with a damp sponge before it hardens.

Once the grout has dried, polish off any haze with a clean dry cloth. If the new grout colour does not quite match the rest of the floor — which can happen if the floor is a few years old and the existing grout has darkened — you can buy grout colourant pens to blend things in. Not perfect, but surprisingly effective.

When to call a handyman

Call Richard if there are multiple tiles lifting or cracking across a wider area, which often points to a problem with the sub-floor or a failing adhesive bed underneath. Replacing one tile is one thing; if the whole floor is starting to sound hollow when you tap it, you are looking at a bigger job. Also worth getting help if the tiles are large format — 600 mm porcelain tiles, for instance, are heavy and unforgiving to cut, and a mistake is expensive.