Bathroom Renovation Cost London 2025: What a Real Renovation Costs

**The six factors that most affect bathroom renovation cost in London**:

**1. Bathroom size**: The single biggest cost driver. A London standard bathroom (approximately 4–6m²) has very different tile, plumbing run, and finishing costs compared with a large family bathroom (8–12m²) or a master en-suite with walk-in shower and freestanding bath. Labour is broadly linear with room area.

**2. Level of strip-out required**: A full strip-out (remove all sanitaryware, tiles, screed, and first-fix plumbing back to the wall) adds £600–£1,500 to the cost but is usually necessary for a proper renovation. A cosmetic-only refurbishment (retile over existing tiles, replace sanitaryware only) is cheaper but limited in what it can achieve and can mask damp or drainage issues.

**3. Plumbing work required**: Moving sanitaryware positions (relocating the toilet, moving the shower to the opposite wall, relocating the basin) is significantly more expensive than replacing in the same positions. Moving the soil pipe requires either access to the floor void below or a macerator pump. London flats with concrete floors are more costly to replumb than timber-floored Victorian houses where pipes can be run in the floor void.

**4. Electrical work**: Bathroom electrical work must comply with Part P of the Building Regulations and, in most cases, must be notified to the LPA (self-notification by an NICEIC or NAPIT registered electrician, or through a third-party Building Control notification). Extractor fan replacement, new heated towel rail connection, underfloor heating, and additional circuits add cost. A Part P completion certificate must be issued and retained.

**5. Specification of sanitaryware and tiles**: This is the primary source of cost variation at the same labour and first-fix quality. Budget tile packs (£15–£30/m²) vs. premium tiles (£80–£200/m²); budget sanitaryware suite (Ideal Standard/Armitage Shanks entry-level, £400–£700) vs. premium suite (Duravit, Villeroy & Boch, £2,000–£6,000+); standard basin tap (£80) vs. bespoke mixer (£600–£1,500). Per RCB's standard terms, **all second-fix materials (tiles, sanitaryware, shower enclosure, taps, towel rail, mirrors, accessories) are supplied by the client**, unless specifically agreed otherwise.

**6. Structural and waterproofing requirements**: Wet room tanking (waterproofing membrane applied to walls and floor before tiling), new joists or floor board replacement where rot or movement is found, and tile backer board installation (recommended over standard plasterboard in wet areas) add £300–£1,500 depending on extent.

**Level 1 — Cosmetic refresh (£3,500–£7,000)**:

Scope: Replace sanitaryware in the same positions (like-for-like toilet, basin, and bath/shower tray); retile over existing tiles OR reglaze existing tiles; replace taps and shower head; new extractor fan; redecorate walls and ceiling; new accessories.

*What is included in RCB labour cost*: Remove old sanitaryware; install new sanitaryware in existing positions; existing plumbing connections reused; retile walls in existing tile configuration; Part P compliant extractor fan replacement; mastic seals and making good. *What is NOT included (client-supplied)*: New sanitaryware; new tiles; new taps; new shower head; new towel rail; accessories; mirrors.

Cost range: £3,500–£7,000 (labour and first-fix materials only, small–medium bathroom)

*What you get*: A refreshed bathroom that looks significantly better but without any structural or layout change. Best where the existing layout works and the main need is updated aesthetics.

**Level 2 — Full renovation, same layout (£7,000–£15,000)**:

Scope: Full strip-out (all sanitaryware, tiles, and first-fix plumbing removed); new first-fix plumbing in the same positions; tile backer board to all wet walls; new floor screed or waterproofed floor substrate; tile all walls and floor to design specification; install all new sanitaryware; Part P electrical work (new circuits as required); new heated towel rail; extraction; redecoration.

*What is included in RCB labour cost*: Full strip-out and disposal; first-fix plumbing; tile backer board; floor preparation and screed (where needed); tiling all surfaces (using client-supplied tiles); sanitaryware installation (using client-supplied items); Part P electrical notification; mastic seals; decoration. *What is NOT included (client-supplied)*: All sanitaryware (bath/shower tray/enclosure, toilet, basin, taps, shower valve, towel rail); all tiles (floor and wall); shower doors/enclosure; mirrors and accessories.

Cost range: £7,000–£15,000 (labour, first-fix materials, and plumbing/electrical materials, medium-sized bathroom)

*What you get*: A completely renovated bathroom with all new first-fix plumbing, electrical, and finishes — but in the same layout as before.

**Level 3 — Full renovation with layout change (£12,000–£22,000)**:

Scope: Everything in Level 2, PLUS relocation of one or more sanitaryware positions (toilet moved to different wall; shower relocated across room; bath removed and replaced with walk-in wet room). Includes all associated structural floor work, new soil pipe routing (where required), and extended electrical runs.

Cost range: £12,000–£22,000 (depending on complexity of layout change, floor structure, and access to pipe routes)

**Level 4 — Luxury bathroom or wet room (£18,000–£35,000+)**:

Scope: Bespoke wet room with full floor-to-ceiling tiling, linear drain, frameless glass screen; freestanding bath with freestanding tap; bespoke vanity unit; underfloor heating with thermostat and Part P certification; bespoke mirror with lighting; full audio/AV integration; premium tile specification.

Cost range: £18,000–£35,000+ (labour and first-fix, excluding premium client-supplied materials — premium sanitaryware and tile packages at this level add £5,000–£20,000+ to client's own material cost)

• **En-suite addition costs** (creating a new en-suite where none existed):
• •Partition wall and door: £600–£1,200
• •Plumbing first-fix for new soil and supply connections: £800–£2,000
• •Electrical (dedicated circuit, extraction, lighting): £400–£900
• •Tiling, waterproofing, and finishing: £1,200–£3,000 (labour)
• •Client-supplied sanitaryware for a compact en-suite: £800–£3,000+
• *Total new en-suite creation (compact, 2–3m²)*: £6,000–£12,000 all-in including all materials

**Building Regulations requirements**:

A full bathroom renovation triggers several areas of the Building Regulations:

*Part P — Electrical safety*: Any new circuit, additional socket, or work in a bathroom 'zone' (zones 0, 1, and 2 around the bath or shower) must comply with Part P. In practice, virtually all bathroom renovations require a Part P compliant electrician (NICEIC or NAPIT registered) who notifies the work to Building Control. A completion certificate must be issued — request it at handover. IP-rated fittings are required in zones 0 and 1.

*Part F — Ventilation*: A bathroom must have mechanical ventilation that provides a minimum extraction rate of 15 l/s when in use (BS EN 15251 and CIBSE Guide A). The extract must discharge to outside air — not into the ceiling void. Timer-overrun is standard. An MVHR unit may be appropriate for highly insulated homes.

*Part H — Drainage*: All waste connections must be adequately sized and fall correctly. Soil pipe connections require inspection access. Any work within 3 metres of a sewer may require a build-over agreement with the sewer authority (now managed by Thames Water or relevant sewerage undertaker).

*No planning permission is normally required* for a bathroom renovation — it is not development under the TCPA 1990 (it does not materially affect the external appearance of the building). Exception: if the property is listed, internal alterations may still require Listed Building Consent.

**Programme**:

• •Cosmetic refresh (Level 1): 3–5 working days
• •Full renovation, same layout (Level 2): 8–12 working days
• •Layout change (Level 3): 12–18 working days
• •Luxury bathroom (Level 4): 15–25 working days

**Choosing a bathroom contractor in London**:

• •Verify the contractor includes a Part P certified electrician in their price (or can confirm how Part P compliance will be notified) — non-compliant electrical work is not just against regulations, it creates liability on sale and voids home insurance
• •Confirm that tile backer board (Wedi, Schlüter Kerdi, or equivalent) rather than standard plasterboard is used on all wet walls — standard plasterboard in a wet area is a common source of later damp and tile failure
• •Confirm that adequate tanking (waterproofing membrane) is applied to the floor and wall/floor junctions in all wet areas, not just the shower tray enclosure
• •Ask whether the quote includes making good to adjoining rooms, ceilings, or walls disturbed by the works