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How to Tile a Bathroom — Step-by-Step UK Guide
Complete guide to tiling a bathroom in the UK, covering waterproofing, layout planning, cutting tiles and grouting for a professional finish.
What You'll Need
Tools
- Manual or electric tile cutter
- Tile nippers and tile file
- Notched trowel (6mm or 10mm depending on tile size)
- Spirit level (600mm and 1200mm)
- Tile spacers (2mm or 3mm)
- Grout float and sponge
- Bucket and mixing paddle
- Silicone gun and finishing tool
- Pencil, tape measure and straight edge
- Diamond hole cutter for pipe holes
- Safety goggles and gloves
Materials
- Wall tiles (allow 10-15% extra for cuts)
- Floor tiles if tiling floor (allow 10-15% extra)
- Flexible tile adhesive (use rapid-set for faster turnaround)
- Waterproof grout
- Tanking membrane kit (liquid or sheet)
- Tanking tape for corners and joints
- Sanitary silicone sealant
- Tile trim for exposed edges
- Tile backer board if walls are not solid (12.5mm)
- Primer/SBR if tiling onto plaster
Before You Start
- Remove existing tiles, loose plaster and any flaking paint. The substrate must be solid, flat and clean.
- Check walls are plumb and flat using a long spirit level. Fill any dips greater than 3mm with a levelling compound or adhesive skim.
- If walls are plasterboard or timber-framed, fix 12.5mm tile backer board (e.g. Hardie Backer or Wedi board) with adhesive and screws.
- Isolate electrics — do not tile near live wiring. Zone 1 and 2 areas have specific IP-rated fitting requirements.
- Plan your tile layout using our Wall Tile Calculator to work out quantities and minimise narrow cuts.
Step-by-Step Instructions
Step 1: Prepare the Substrate
Remove all old tiles, adhesive residue and loose material. Skim-coat any rough plaster. If tiling onto bare plasterboard, apply a coat of SBR primer diluted 1:4 with water and allow to dry. This seals the board and improves adhesion.
Step 2: Waterproof Wet Areas
Apply liquid tanking membrane to all areas that will receive direct water — the shower enclosure, around the bath, and behind the basin. Apply two coats with a brush or roller, allowing 2-4 hours between coats. Bed tanking tape into the first coat at all internal corners, floor-to-wall joints, and around pipe penetrations.
Step 3: Set Out Your Layout
Dry-lay a row of tiles along the most visible wall to plan the layout. Aim for balanced cuts at each end — avoid slivers less than half a tile width. Mark a horizontal datum line one tile height above the bath or floor using a spirit level. Start tiling from this line upwards.
Step 4: Fix a Temporary Batten
Screw a straight timber batten along your datum line. This supports the first row of tiles while the adhesive sets. Remove it later and tile the bottom row last.
Step 5: Apply Adhesive and Lay Tiles
Spread flexible tile adhesive onto the wall using a notched trowel — work in areas of about 1m² at a time so the adhesive does not skin over. Press each tile firmly into the adhesive with a slight twisting motion. Use tile spacers between every tile. Check regularly with a spirit level.
Step 6: Cut Tiles
Measure and mark each cut tile individually — walls are rarely perfectly square. Use a manual tile cutter for straight cuts and a diamond hole cutter for pipe holes. For L-shaped cuts, score with a tile cutter and nibble away waste with tile nippers. Smooth rough edges with a tile file.
Step 7: Tile the Bottom Row
Once the upper tiles have set (24 hours minimum), remove the batten and tile the bottom row. Cut tiles to fit the gap, leaving a 3mm expansion gap at the floor for silicone.
Step 8: Grout
Mix waterproof grout to a smooth paste. Apply with a grout float held at 45° to the tiles, pressing grout firmly into every joint. Work diagonally across the tiles. After 15-20 minutes, wipe off excess with a damp sponge, rinsing frequently. Shape joints with a rounded grout finisher if desired. Use our Grout Calculator to estimate grout quantities.
Step 9: Seal with Silicone
Apply masking tape either side of all internal corners, floor joints and around sanitaryware. Run a bead of sanitary silicone and smooth with a finishing tool or wet finger. Remove masking tape immediately before the silicone skins over.
Step 10: Final Clean-Up
After 24 hours, polish off any grout haze with a dry cloth. Re-fit accessories, shower screens and trims. Allow silicone to cure for at least 24 hours before using the shower or bath.
Common Mistakes to Avoid
- Skipping waterproofing: Tiles and grout are not waterproof. Without tanking, water will penetrate and cause rot, mould and damage to adjoining rooms.
- Not checking levels: Even small deviations compound over many rows. Check every 3-4 rows with a spirit level.
- Using rigid adhesive on flexible substrates: Timber-framed walls and backer board need flexible adhesive — rigid adhesive will crack.
- Grouting internal corners: These joints must be silicone, not grout. Grout will crack as the building moves.
- Tiling over damp walls: Fix any damp issues before tiling. Tanking is for splash water, not rising damp or penetrating damp.
Cost Estimate (2026 UK Prices)
| Item | Typical Cost |
|---|---|
| Ceramic wall tiles (per m²) | £12-£30 |
| Porcelain wall tiles (per m²) | £25-£60 |
| Tile adhesive (20kg bag, covers ~5m²) | £15-£25 |
| Waterproof grout (5kg bag) | £10-£18 |
| Tanking kit (10m² coverage) | £40-£70 |
| Tile backer board (per sheet 1200×800mm) | £15-£30 |
| Sanitary silicone (per tube) | £5-£10 |
| Total for a standard bathroom (DIY, ~12m² walls) | £350-£900 |
Use our Wall Tile Calculator, Tile Adhesive Calculator and Grout Calculator for exact quantities for your project.
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Frequently Asked Questions
Yes. Any area that will be regularly exposed to water — shower zones, around the bath and behind the basin — should be tanked with a liquid waterproofing membrane. Tiles and grout alone are not waterproof. Use a brush-on tanking kit such as BAL Tank-it or Mapei Mapelastic, applying two coats with tape on internal corners and joints.
Large-format tiles (300×600mm or 600×600mm) actually make a small bathroom feel bigger because there are fewer grout lines. However, they are harder to cut and need a very flat substrate. For shower floors, use smaller mosaic tiles (50×50mm or similar) to follow the gradient to the drain.
Allow the tile adhesive to cure for at least 24 hours before grouting. In cold or damp conditions, extend this to 48 hours. Using a rapid-set adhesive can reduce waiting time to 3-6 hours, depending on the product.
Always use silicone sealant in internal corners, where walls meet the floor, and around the bath or shower tray. These joints need to flex — grout will crack. Use a colour-matched sanitary silicone for a neat finish.
Measure the total area to be tiled in m² and add 10-15% for cuts and waste (more for diagonal layouts or complex shapes). Use our Wall Tile Calculator for an accurate quantity based on your tile size and room dimensions.
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Last updated: April 2026
Verified against UK standards · estimates only, confirm with your supplier.