DIY GUIDE · HOME REPAIRS & HANDYMAN · CHECKED OCTOBER 2026
How to regrout tiles yourself
A day for a shower wall, plus a day to cure. €20–€45 in grout and tools.
Rake out the old grout, mix the new to the sheet, fill, clean at the right moment and let it cure — walls and floors.
- Every step, start to finish
- Checked October 2026 — sources at the end
- Honest about when to call a pro
FIRST, THE HONEST ANSWER
Do it yourself, or get a handymen?
Do it yourself if…
- The tiles are sound and firmly stuck; only the grout is dirty, cracked or missing
- You are regrouting a splashback, a bathroom wall, a shower or a small floor
- You can work patiently with a hand rake for a few hours
- The shower or room can be out of use for a day while the grout cures
Get a pro if…
- Tiles sound hollow when tapped, move, or are cracked — the problem is behind them, not the grout
- Water has got behind a shower wall and the board or plaster is soft or stained
- It is a large floor, natural stone that stains easily, or a wet room with a tanked floor
- The tiles or their adhesive are in an older house and may contain asbestos
Safety first
- Wear safety glasses and a dust mask when raking out; old grout dust is fine and irritating, and a power tool makes much more of it.
- Wear gloves when mixing and handling cement grout, which can irritate and burn skin. Wash it off promptly with water.
- Isolate sockets on a splashback at the fuse board before raking near them, and keep water away from them while cleaning.
- Ventilate the room while using mould removers and do not mix cleaning products; the HSA’s chemicals guidance is to read the label and safety data.
- In an older house, old tile adhesives and floor tiles may contain asbestos. Do not sand, drill or grind them; get them checked first.
| MATERIAL | COVERAGE | FOR THIS JOB |
|---|---|---|
| Cement-based tile grout | Bag sized to the area, joint width and tile size | Worked out with the calculation below |
| Mould remover or tile cleaner | One bottle | For cleaning the tiles before you start |
| Flexible silicone sanitary sealant | One cartridge | For corners and edges at baths, trays and worktops |
How much grout do you need?
One grout maker’s formula is: kg per m² = (tile length + tile width) ÷ (tile length × tile width) × tile thickness × joint width × 1.6, all in millimetres. For 200 × 200 mm tiles, 7 mm thick, with 3 mm joints: (200 + 200) ÷ (200 × 200) × 7 × 3 × 1.6 = 0.34 kg per m². A shower enclosure with 8 m² of tiling needs about 2.7 kg, so a 5 kg bag covers it with spare for mistakes.
Allow extra for waste in the bucket and on the float, and buy it all in one colour batch.
Every grout is made for a range of joint widths. One widely sold cement-based grout covers joints from 2 to 20 mm, so it suits most wall and floor tiles; ready-mixed tub grouts are often for narrow wall joints only. Read the width on the bag before you buy, and measure your joints with a ruler first.
Powder grout mixed with water is strong, cheap and comes in many colours, including flexible and water-repellent versions for showers and heated floors. Ready-mixed tubs are convenient for small wall repairs but are softer. Epoxy grout resists stains and acids and suits worktops and showers, but it sets fast and is hard to clean off — not a first job.
The joints at internal corners, where the tiles meet the bath, tray or worktop, and any movement joints in a floor are filled with flexible silicone sealant, not grout. Grout in those joints cracks as the building moves. One grout maker says plainly that expansion and movement joints must never be filled with its grout.
A carbide-tipped hand rake is slow but gives you control, and is the safer way round tile edges. A multi-tool with a grout blade is faster on long runs, but it chips glazed edges in a moment and throws fine dust. Whichever you use, the aim is the same: get the joint clean to a good depth without touching the tiles.
Grout dries lighter than it looks wet. White shows dirt quickly on floors; mid-greys hide it. If you are only regrouting part of a wall, matching old grout exactly is unlikely — regrout the whole area, edge to edge, so there is no patchwork.
THE PART THAT DECIDES THE FINISH
Preparing the tiles — by where they are
The raking and filling are the same everywhere, but the preparation changes with the room. Pick the card that matches.
Shower walls and bath surrounds
Grout black with mould or cracked, often with tired silicone along the bottom.
- Stop using the shower for at least a day beforehand so the joints are dry
- Cut out the old silicone at the tray or bath with a sharp blade and peel it away
- Clean the tiles with a mould remover, rinse and let them dry
- Tap the tiles: any that sound hollow or move need refixing first
Kitchen splashbacks
Greasy, stained grout behind the hob and the sink.
- Degrease the tiles and joints with hot water and a strong detergent, then rinse
- Mask the worktop and the hob with tape and paper
- Isolate any socket on the splashback at the fuse board before you rake near it
- Check the joints at the worktop are sealant, not grout
Floors
Grout worn low, cracked or dirty in a hall, kitchen or bathroom floor.
- Clear the room and vacuum the floor thoroughly
- Check for movement joints at doorways and long runs — they get sealant, not grout
- Plan an exit so you do not have to walk on the new grout
- Check whether the floor is heated; if so, use a grout rated for it and switch the heating off
Grout that is stained but sound
Discoloured joints that are still hard and complete.
- Clean a small area with a grout cleaner and a stiff brush first
- If it comes up, clean the rest and seal it
- If it does not, a grout colour pen covers it on walls
- Only rake out if the grout is soft, cracked or missing
THE JOB
How to regrout tiles, in order
Prepare the room and clean the tiles
30 minClear the area, mask anything you do not want grout on, and lay dust sheets. Clean the tiles and the old grout with mould remover or detergent as the card above suits, rinse and let it all dry. Cut out old silicone at the bath, tray or worktop. Put on safety glasses and a dust mask.
- Open a window and keep the bathroom door shut to keep dust in the room
- Cover the plughole and the shower tray with tape so grout cannot go down the waste
- Have the vacuum ready before you start raking
Mistake to avoid: Raking out before cleaning the mould. The spores go into the air and the fresh grout goes in over a dirty edge.
Rake out the old grout
3–4 hrHold the rake like a pencil, at a shallow angle, and draw it along the middle of each joint without letting it touch the tile edges. Work the verticals first, then the horizontals. Go back over each joint until it is clean to a good depth — one grout maker asks for joints free of dust and empty to at least two-thirds of the tile’s thickness. Vacuum the joints as you go.
- Let the rake do the work in short, light strokes; pressing hard chips glaze
- Change the blade when it stops cutting
- If a tile edge chips, stop and change your angle before you go on
Mistake to avoid: Raking out only the surface. New grout bonded to a thin skin of old one cracks out within months.
Vacuum and check the joints
20 minVacuum every joint and wipe the tiles with a barely damp cloth. Look along each joint with a torch held flat to the wall: you want clean, even channels. Check no tile has loosened while you raked. On very absorbent tiles or a warm, breezy day, dampen the joints lightly with a sponge just before you grout, as the grout maker suggests.
- Run a fingertip along the joints to find any lumps of old grout
- Let damp joints dry to just damp, not wet
- Refix any loose tile with tile adhesive and leave it to set before grouting
Mistake to avoid: Grouting over dust. The new grout cannot bond, and powders out of the joint.
Mix the grout exactly
10 minMeasure the water first. One maker’s powder grout needs 22-26% water by weight — a 5 kg bag takes roughly 1.1 to 1.3 litres — poured into a clean bucket, with the powder added while you stir. Mix to a smooth, lump-free paste, let it stand for 2-3 minutes, then stir briefly again. Mix only as much as you can use within its pot life — 20-25 minutes for that grout.
- Use clean water and a clean bucket; dirty water changes the colour
- Mix slowly so you do not whip in air
- Work at room temperature — the same maker gives a range of 5°C to 35°C
Mistake to avoid: Adding water to grout that has started to stiffen. It weakens and changes colour; throw it away and mix fresh.
Fill the joints
30 minScoop grout onto the float and press it into the joints, holding the float at about forty-five degrees and sweeping it diagonally across the tiles. Work in an area of about a square metre. Go over each joint twice to push the grout in fully, with no gaps or pinholes. Then hold the float almost upright and scrape the surplus off diagonally to the joints.
- Diagonal strokes stop the float edge dragging grout out of the joints
- Keep the float edge clean so it does not smear
- Leave the internal corners and the bath or tray edge empty for sealant
Mistake to avoid: Spreading a whole wall before cleaning any of it. The first area sets hard on the tiles before you get back to it.
Sponge off at the right moment
30 minWatch the grout. When it has lost its shine and gone matt — one maker says after 15-30 minutes — wring out the sponge until it is just damp and wipe diagonally across the joints in light strokes. Rinse the sponge in the first bucket, and use the second, clean bucket for the final rinse. Re-strike any joint that the sponge has dished with a rounded tool or a fingertip.
- Too wet a sponge pulls grout out of the joints
- Turn the sponge often so you always wipe with a clean face
- Change the rinse water as soon as it turns cloudy
Mistake to avoid: Cleaning too soon. The sponge drags wet grout out and leaves hollow joints.
Even the joints and buff the haze
20 minWhen the grout is partly set — the same maker gives 50-60 minutes — you can lightly even out the surface with a damp, non-scratch pad. Later, when it is dry to the touch, buff the powdery haze off the tiles with a clean, dry cloth.
- Polish in circles with a dry cloth, not a damp one
- Check the joints at an angle against the light for missed spots
- Stubborn haze after curing can be lifted with the cleaner the grout maker recommends
Mistake to avoid: Leaving the haze to cure on the tiles. It bonds and becomes much harder to remove.
Cure, then seal the edges
24 hrLeave the grout to cure. One maker’s grout takes light foot traffic after about 3 hours and is ready for use after 24 hours, or 48 hours for basins and swimming pools. In hot, dry weather, dampening the joints lightly after a few hours helps it cure. Once cured, run a bead of flexible silicone sealant along the internal corners and the joint at the bath, tray or worktop.
- Keep the shower out of use until the grout is fully ready
- Use sanitary silicone for wet areas; it contains a fungicide
- Wipe the shower walls dry after use for the first weeks to keep the new grout clean
Mistake to avoid: Filling the corner and bath joints with grout. They crack as soon as the bath fills and moves.
The mistakes that make it worse
- Raking only the surface of the old grout
- Using a blade wider than the joint and chipping the tiles
- Adding water to grout that has started to set
- Sponging before the grout has gone matt
- Grouting the corners and the joint at the bath instead of sealing them
Stop here and get a tiler
- Tiles are hollow, loose or cracked across a large area
- The wall or floor behind is soft, stained or wet
- It is natural stone that needs sealing and special grout, or a tanked wet room
- The old tiles or adhesive may contain asbestos
| WHAT YOU SEE | WHY, AND THE FIX |
|---|---|
| New grout cracking within weeks | The old grout was not raked deep enough, the mix was too wet, or the joint is a movement joint. Rake out the cracked runs fully and regrout, and use silicone in corners and at edges. |
| Grout is patchy or different colours | Water was added unevenly, a batch was remixed, or the sponge was too wet. Small patches can be re-raked and refilled; buy one batch and measure the water next time. |
| White haze on the tiles | Grout film left to dry. Buff with a dry cloth; if it has cured, use the cleaner the grout maker recommends after the stated wait. |
| Pinholes in the joints | Air in the mix or not enough pressure with the float. Fill them with a little fresh grout pressed in with a fingertip. |
| Chipped tile edges | The rake touched the tile. Small chips can be touched in with a tile repair pen; slow down and keep the blade centred. |
| Grout washes out when sponging | Sponging too early, or with too wet a sponge. Wait until the grout goes matt and wring the sponge harder. |
| Grout goes black again quickly | Shower left wet, or the corners were grouted instead of sealed. Ventilate, wipe the walls after showers, and seal the corners with sanitary silicone. |
| Tiles sound hollow after raking | The adhesive behind has failed. Lift and refix them before grouting, or get a tiler if many are loose. |
WHAT YOU SAVE
What it costs to do it yourself
| Flexible tile grout, 2.5kg | €11–€13.95 |
|---|---|
| Wall and floor grout, 5kg | €20–€25.90 |
| Grout rake or remover | €5–€13 |
| Grout sponge kit | €9 |
| Sanitary silicone sealant, 280ml | €13 |
| Mould remover, 500ml | €8–€9.65 |
| Total, a shower wall | €20–€45 |
| DIY total | €20–€45 |
Guide prices compiled by the Locufy team from published Irish and UK provider price lists and 2026/27 cost guides. Updated 2026.
Grout and tools for a shower or splashback cost far less than a tiler’s day; a powered grout remover is only worth buying for a big job.
RATHER NOT?
Tilers near you, with prices shown
The ones who cover your area, nearest first, with one score from every review. No account needed to look.
Or post the job free and let them come to you.
Give the grout the full time on the bag before the shower is used or the floor is washed. Damp-curing it lightly in hot weather helps.
Wipe shower walls after use, ventilate the bathroom, and clean the grout with a mild cleaner rather than bleach, which can fade coloured grout.
Let leftover grout set hard in its bucket and put it in the general waste in small amounts — never wash it down a drain. Larger amounts of old grout, adhesive and broken tile are rubble: take them to a civic amenity site that accepts it, which the mywaste.ie locator lists.
Wash the float, bucket and sponge in clean water before the grout sets; set grout is very hard to remove.
Regrouting tiles: questions people ask
Deep enough for the new grout to hold. One grout maker asks for joints clean and empty to at least two-thirds of the tile’s thickness. A thin skin of new grout over old soon cracks out.
Not successfully. A thin layer has nothing to grip and cracks. Rake out to a good depth, or clean and colour sound grout instead.
Follow the bag. One maker’s grout is ready for use after 24 hours, or 48 hours for basins and pools, with light foot traffic on floors after about 3 hours.
Silicone. Internal corners, the joint at the bath or tray, and the joint at a worktop move, and grout there cracks. Use flexible sanitary silicone.
Buff it off with a dry cloth once the grout is dry to the touch. If it has cured hard, use the cleaner the grout maker recommends, after the time it states.
On the Locufy price guide for Ireland, grouting and regrouting costs €200–€450 per job, typically €280. A splashback is at the low end; a full bathroom or a large floor at the top.
MORE GUIDES
More DIY guides
Sources — checked October 2026
- Mapei — Ultracolor Plus technical data sheet: joints 2 to 20 mm, 22-26% water, pot life, cleaning times, curing, consumption formula
- HSA — chemicals
- HSA — asbestos
- MyWaste — what to do with rubble
- diy.ie — tile grout, price check October 2026
- diy.ie — grout rakes and removers, price check October 2026
- diy.ie — mould removers and sealant, price check October 2026