How to re-grout tiles

Inspired by a helpful YouTube guide. This walk-through is based on the "How to re-grout tiles" video produced in collaboration by Tile Warehouse and UK DIY YouTuber ProperDIY. It is one of the more honest tutorials out there — it does not skip the grout removal stage, which is where most re-grouting guides fall apart. Worth watching before you buy your grout rake.

1. Identify which grout needs replacing

Go around the tiled area with good light and look closely at the joints. Cracked grout, darkly stained sections that will not clean up, and any joints where the grout has shrunk away from the tile edge are all candidates for removal. You do not have to regrout every joint — just the ones that are failing.

Run a finger along the joints. If grout crumbles or flakes easily, it has lost its bond. If it feels solid and just looks dirty, a proper clean with a tile grout restorer pen or a specialist cleaner might be enough to avoid the whole job.

2. Remove the old grout carefully

A grout rake is the basic tool — a handle with a carbide tip that cuts through the old grout when dragged along the joint. Slow, steady strokes work better than forcing it. The goal is to remove most of the old grout without scratching the tile edges.

For a larger area, an oscillating multi-tool with a grout removal blade makes the job much faster. Mind you, it is noisier and takes more care on soft or natural stone tiles, which are easier to chip. Keep the tool moving and avoid dwelling in one spot.

3. Vacuum and clean the joints thoroughly

Once the old grout is out, vacuum along every joint to clear the dust and debris. Then wipe the area with a damp cloth and leave it to dry completely. Any moisture or loose dust left in the joint will prevent the new grout from bonding properly.

Check for any signs of damp, mould behind the tiles, or loose tiles. Re-grouting over a damaged substrate just delays a bigger job. If tiles are hollow when tapped or move under light pressure, the adhesive behind them has failed and they need to come off properly before re-grouting can start.

4. Mix your new grout

Choose a grout to match or slightly improve on the original colour. Grout colours vary between brands, so buy a shade or two lighter if you are not sure — grout dries lighter than it looks when wet. Mix to a smooth, thick consistency following the packet instructions.

Work in small batches. Grout has a working time of around 20 to 30 minutes once mixed, after which it starts to stiffen. Mixing too much at once means half of it sets in the bucket while you are still working on the wall.

5. Apply grout with a rubber float, working diagonally

Load the float with a reasonable amount of grout and sweep it across the tiles at roughly 45 degrees to the joint lines. Diagonal strokes fill the joints more efficiently and leave less excess grout sitting on the tile face than going straight across.

Work on sections of about a square metre at a time so you can clean each section before moving to the next. Larger areas are fine once you are more confident, but starting in manageable sections means the first section will not have set hard before you get back to clean it.

6. Press firmly into every joint

Go back over each section and press the grout firmly into the joints using the edge of the float. Any voids or air pockets will show as dark spots once the grout dries. Take your time on this stage — a solid joint is a watertight joint.

Use the float to scrape off as much excess grout as you can from the tile faces while it is still soft. The more you remove here, the less work the sponge has to do and the better the finished result.

7. Clean the tile faces before the grout sets

Using a damp (not soaking) sponge, wipe the tile faces in a circular motion to remove the grout film. Rinse the sponge frequently in clean water and change the water as soon as it turns grey. Dirty water moves grout around rather than removing it.

Do not press so hard that you pull grout out of the joints. Light, steady wiping is all it needs. The joints may look rough at first — that is normal and settles as the grout cures.

8. Leave to cure before getting the area wet

Most standard grouts need 24 hours before light use and 48 to 72 hours before the area gets wet regularly. Check the packaging. In bathrooms and shower enclosures, the joints where tiles meet the bath, tray, or shower tray should be finished with sanitary silicone rather than grout — those corners flex slightly in use and grout will crack there every time.

Once fully cured, buff the tiles with a dry cloth to remove any remaining haze. Glazed and polished tiles come up cleanly; textured tiles may take a little more work with a soft brush.

When to call a handyman

Call Richard if the tiles themselves are loose, if there is damp behind the surface, or if you have a large area to tackle and not much time. The Sandwich Handyman can help with re-grouting, silicone sealing, and bathroom tile repairs in Sandwich and across East Kent.