Do I need building regulations for a bathroom?

Building Regulations apply to electrical work in bathrooms under Part P (work must be done by a registered electrician and certified), to extraction (Part F requires mechanical ventilation in any bathroom without an opening window), and to drainage where soil pipes are altered. You do not need a Building Notice for like-for-like replacement of fixtures in the same locations. Always insist on Part P certification and a Notice of Completion from the building control body — your home insurance and onward sale will require this.

How much does adding a second bathroom cost in London?

Adding a bathroom to an existing room (former dressing room, large bedroom corner, under-stairs cupboard) costs £9,000-£18,000 if waste and water can reach within 6 metres. Adding a bathroom requiring a new soil stack or floor cut adds £3,000-£6,000. A new ensuite in a loft conversion is usually included in the loft conversion price and adds £4,500-£8,000 incremental cost. Always confirm Part B fire safety implications when reducing bedroom count via internal subdivision.

What's the cheapest way to renovate a London bathroom?

Keep layout identical, retain existing tiles below dado and replace only those above, re-grout floor tiles rather than retile, replace only WC and basin (retain bath), update brassware. Realistic budget £2,800-£4,500 for a cosmetic refresh of a 4m² bathroom. This is around 25-30% of a full strip-out cost and delivers 50% of the visual upgrade. Avoid this approach if there are signs of leak damage, mould behind silicone, or pre-2002 lead pipes — full strip-out is then essential.

Should I use a wet room or traditional bathroom?

Wet rooms (fully tanked floors with glass screen, no shower tray) cost £2,000-£4,500 more than a traditional bathroom of the same size due to additional tanking, gradient floor screed and drainage. They are best in smaller bathrooms (under 5m²) where space saving is significant, and in master suites where the aesthetic premium matters. Traditional bathrooms with bath/shower combination remain better for resale on family homes — most London estate agents will down-value a property with only a wet room if there are no other bath options in the house.

Bathroom Renovation Cost London 2026 | Builderr

How Much Does a Bathroom Renovation Cost in London?

A standard London bathroom renovation costs £8,500–£15,000 with mid-range fixtures (Roca, Hansgrohe) and porcelain tiles. Premium bathrooms with bespoke vanity, natural stone and underfloor heating run £18,000–£32,000. Average installed cost: £2,800–£4,500 per square metre of bathroom floor area, fully fitted.

What is included in a bathroom renovation cost?

A turnkey London bathroom renovation includes strip-out and disposal of existing fixtures and finishes, soil pipe and waste reconfiguration if needed, hot and cold water re-routing, electrical first and second fix including extractor and lighting, plasterwork, full waterproofing under tile (tanking), wall and floor tiling, sanitaryware (WC, basin, bath or shower), brassware (taps, shower controls, valve), vanity unit, mirror, accessories, decoration to ceilings and any non-tiled walls, and final cleaning. Optional and quoted separately on most jobs: underfloor heating (£800-£1,800 fitted on a 4-6m² floor), heated towel rail (£250-£900), bespoke joinery vanity (£1,500-£4,000 vs £400-£900 stock), full-pane glass shower screens (£600-£1,800), niche shelves cut into walls (£300-£600 each), and structural changes to enlarge the room.

Cost by bathroom tier

Three tiers cover most London bathroom refurbishments. Entry-level (£8,500-£14,000): mid-market Roca, Twyford or Ideal Standard fixtures, porcelain wall and floor tiles £25-£45/m², standard chrome brassware, stock vanity, no underfloor heating. Mid-range (£14,000-£22,000): Hansgrohe, Crosswater or Aqualisa brassware and showers, full-height porcelain or ceramic tiling £45-£90/m², underfloor heating, larger format tiles, stone resin shower trays, custom-cut vanity. Premium (£22,000-£32,000+): natural stone tiles £120-£300/m², brass or copper fittings (Drummonds, Burlington, Lefroy Brooks), bespoke joinery vanity, walk-in steam shower, Smart heating controls, mood lighting circuits. Above £32,000, bathrooms overlap with spa-grade master suite builds where structural enlargement, Hammam-style finishes and high-end stone push costs to £60,000-£100,000.

What drives bathroom cost variance?

Tile choice is the single biggest variable: ceramic at £25/m² versus marble at £250/m² creates an £2,000-£4,000 swing on the same footprint. Brassware bracket is second: a complete Roca brassware set (taps, shower, valve, waste) runs £400-£700; the same set in Hansgrohe Axor or Vola is £2,400-£3,800. Layout change (moving WC, swapping bath for walk-in shower) adds £1,500-£3,500 in waste reconfiguration and re-tile. Underfloor heating adds £900-£1,800 fitted. Bespoke joinery vanity replacing stock unit adds £1,200-£3,500. Always price a fixed-scope bathroom against a written specification — most disputes arise from PCs on tile and brassware where allowances are quoted at entry-level prices but real selections sit one or two tiers up.

Realistic London timelines

On-site duration for a standard bathroom renovation in London is 12-18 working days for a like-for-like swap, 18-28 days for layout reconfiguration including new waste runs, and 28-40 days for full reconfigurations involving structural work or master ensuite enlargement. Tiling alone consumes 3-7 days depending on tile size, pattern and substrate prep. Plan total project duration including specification, ordering and lead times of 8-14 weeks. Lead times for ordered fixtures and bespoke joinery routinely exceed site duration — order everything before site start and store at the contractor's premises to avoid mid-build delays.