Regrouting

• Cracked or crumbling grout: Often along a shower wall or where the wall meets the tray.
• Missing grout: Gaps that let water straight behind the tiles.
• Mould that will not clean off: Black spots that have grown into the grout, not just on its surface.
• Discoloured grout: Staining that cleaning no longer shifts.
• Water getting through: Damp patches on the other side of the wall, or stains on the ceiling below a shower.

If tiles also sound hollow when tapped, move, or are cracked, they need refixing or replacing cracked or chipped tiles before regrouting. Grout cannot hold a loose tile in place.

Not properly. New grout spread over the top of old grout is only a thin skin. It does not bond well, cracks and flakes off, and traps any mould underneath. The old grout has to be raked out to a good depth first, so that the new grout forms a solid joint. Grout pens and colour paints can freshen sound grout, but they do not repair cracks or gaps.

1. 1

   Check the tiles: we tap for hollow or loose tiles and look for signs of water behind them.

2. 2

   Remove silicone: old silicone at the bath, tray and worktop is cut out so the joints can be cleaned.

3. 3

   Rake out: the old grout is removed with a grout rake or a powered tool with a carbide blade, taking care not to chip the tile edges.

4. 4

   Clean: dust and loose material are vacuumed out, and mould is treated so it does not come back through the new grout.

5. 5

   Regrout: fresh grout is pressed firmly into every joint, tooled to a neat finish and the haze cleaned off the tiles.

6. 6

   Cure and seal: once the grout has cured, cement grout in wet areas is sealed through our sealing tile joints for waterproofing service.

7. 7

   Reseal the junctions: fresh, flexible siliconing where tiles meet the bath, tray or worktop.

The shower or floor must stay out of use until the grout has cured. We tell you when it is ready.

For a shower that gets heavy daily use or a kitchen worktop, epoxy is worth considering. For most bathroom walls, a good mould-resistant cement grout, sealed afterwards, works well.

Regrouting is the time to change colour. Light grey hides floor staining better than bright white, and a contrasting grout makes metro tiles stand out. Pigment can mark some tile surfaces, so we test darker grout on a spare or hidden tile first.

There is no fixed interval. A well-ventilated shower with sealed grout that is wiped down after use can go a long time; a busy family shower with poor extraction will need it sooner. Look for the signs above when you clean. If your bathroom has no working fan, one can be fitted through our domestic electrical installation service.

If water has been getting behind the tiles for a while, the background may be wet or soft. Regrouting stops new water getting in but does not repair the wall. Where damp patches or stains below suggest a leaking pipe or valve, our leak detection and pipe repairs service finds the cause first. If the shower was never tanked, retiling through our installing kitchen and bathroom tiles service may be the lasting answer.