Bathroom Renovation — A Complete Guide to Planning, Sequence and Costs

**Level 1 — Refurbishment (like-for-like suite replacement)**: Sanitaryware (bath, toilet, basin, shower) replaced in the same positions. Tiles cleaned or replaced where they run behind the old suite. Taps, shower, and mixers replaced. No rerouting of pipework. Typical cost: £5,000–£9,000 Disruption: 1–2 weeks

**Level 2 — Full renovation (new layout, full retile)**: All sanitaryware replaced; layout changed; full strip-out of existing tiles, floor, and potentially some plasterboard; new waterproofing; new first-fix plumbing to new positions; full retile to walls and floor; new electrics (lighting, extractor, shaver sockets, towel rail); new sanitaryware installed. Typical cost: £9,000–£18,000 Disruption: 2–4 weeks

**Level 3 — Full renovation with luxury specification**: All of Level 2 plus: designer sanitaryware (freestanding bath, designer shower enclosure, concealed cistern); bespoke furniture units; underfloor heating; large-format porcelain tiles with minimal grout joints; heated towel rail; designer taps and mixers; smart shower system. Typical cost: £16,000–£28,000+ Disruption: 3–5 weeks

**En-suite addition**: See: en-suite addition guide. Typically £8,000–£25,000+ depending on size and specification.

The sequence of a bathroom renovation must follow a strict technical order:

1. **Strip-out**: remove all existing sanitaryware, tiles, floor coverings, and any plasterboard that is damp, damaged, or in the wrong position. Leave the structural shell. 2. **First-fix plumbing**: reroute supply pipes and waste pipework to the new positions. Soil pipe connections must be confirmed before this stage. If drainage must be altered, this may involve breaking the floor slab or lifting floorboards. 3. **First-fix electrics**: new wiring for lighting (IP65-rated in Zones 0–2), extractor fan, shaver socket, towel rail connection, and underfloor heating (if electric mat UFH is specified). All wiring hidden before the next stage. 4. **Waterproofing / tanking**: apply waterproofing system (tanking slurry or Wedi or Schluter system) to all wet areas — shower enclosure, around the bath, floor. Allow to cure. 5. **Wall boarding**: where plasterboard has been removed, new moisture-resistant plasterboard (or tile backer board) is fixed. Tile backer board (Wedi, Jackoboard, or Hardiebacker) in wet areas is strongly preferred to moisture-resistant plasterboard. 6. **Screeding (if UFH is involved)**: if water underfloor heating is installed in the floor, the floor screed goes now before tiling. Allow 7–14 days to cure before tiling on the screed. For electric mat UFH, this typically goes directly beneath the tile adhesive. 7. **Wall tiling**: walls tiled from the correct datum line. Allow at least 24 hours for adhesive to cure before grouting. Large-format tiles require a fully flat wall substrate. 8. **Floor tiling**: floor tiled after wall tiling is complete (so grout doesn't need to be cleaned off floor tiles). Allow 24–48 hours before walking on the floor. 9. **Grouting**: grout all tiles; sealant (silicone) at movement joints (floor-to-wall junction, any internal corners). 10. **Sanitaryware installation (second-fix plumbing)**: bath, basin, toilet, and shower enclosure installed; taps, mixers, and shower connected. 11. **Second-fix electrics**: light fittings, extractor, shaver socket, and heated towel rail connected; Part P certificate issued. 12. **Final fit-out**: mirrors, accessories, shower screen, glass panels; sealant around bath and shower enclosure. 13. **Snagging**: check all connections, test extractor, flush all outlets, check shower temperature and flow, inspect grout lines and sealant.

**Labour**: plumber, electrician, tiler, and carpenter are the core trades. In London, a bathroom renovation by a quality contractor takes 2–4 weeks for a full renovation — with day rates of £250–£400 per trade. The total labour component is typically £4,000–£10,000.

**Sanitaryware**: bathroom suites vary from £300 (basic) to £5,000+ (designer/luxury). Freestanding baths (£500–£5,000+), walk-in shower trays with frameless enclosures (£500–£3,000+), and concealed cistern units (£200–£600) are the key cost variables in sanitaryware.

**Tiling**: the tile material cost varies from £15–£80+ per m². The labour cost is similar whether cheap or expensive tiles are used — the skill is in the installation. For a standard bathroom of 5m², wall and floor tiling materials range from £500 (basic) to £4,000+ (large-format designer porcelain). Large-format tiles require more skilled installation (levelling system, larger-format cuts) — expect higher labour costs.

**Drainage complexity**: relocating a soil pipe connection or breaking through a concrete floor to reroute drainage is one of the most significant cost items in a bathroom renovation — typically £1,000–£2,500 additional.

**Boiler and hot water system compatibility**: if the existing hot water system cannot supply the required flow rate and pressure for a new shower system (especially for a high-pressure rainfall shower), additional work (a pump, or a new unvented cylinder) may be required — add £500–£2,000.

**Sanitaryware selection before works start**: the plumber must know the exact make and model of bath, toilet, basin, and shower tray before first-fix plumbing — because waste outlet positions and supply pipe positions are specific to the product. Changing the product after first-fix means moving pipes.

**Shower type and specification**: over-bath shower, walk-in shower enclosure, wetroom, or combination? The floor construction (wetroom requires a floor drain and fully tanked floor to a fall) is determined by this decision.

**Tile selection before tiling starts**: tiles must be on site before tiling starts. Order with 10–15% overage to allow for cuts and breakages. Large-format tiles require a flatter substrate and additional preparation.

**Extraction**: bathrooms must have mechanical ventilation. Extractor fans must vent to external air — through the wall or ceiling. The route must be confirmed before first-fix electrics.

**Underfloor heating decision**: UFH is best installed at the beginning of the project — retrofitting it after tiling requires removing the tiles. Decide before work starts.