Bathroom Fitters London

A bathroom is the smallest room in a London house and the one that goes wrong most expensively. It is the only room where five trades work in a space the size of a parking bay, and the only one where a hidden mistake shows up as a stain on the ceiling below eighteen months later. GS Renovation fits bathrooms, en-suites, shower rooms and wet rooms across Central and Greater London, and this page is about the parts of the job you cannot see once the tiles are on.

What a proper bathroom fit involves

Stripping a bathroom out is a day's work. What follows is what separates a fit that lasts twenty years from one that needs redoing. The order below is not negotiable, and any fitter who offers to skip a stage of it is offering to save you money you will spend twice.

• Strip out to the substrate, then inspect what is behind. Old joists, perished pipework and previous leaks all show up at this point, not later.
• Alter waste and supply pipework to suit the new layout, with proper falls on every waste run so the room drains rather than pools.
• Board and tank the wet areas. Tile backer board and a liquid or sheet tanking membrane behind the shower, not tiles stuck straight onto old plaster.
• Electrics designed to the correct zones, in bathroom-rated fittings, notified under Part P and certified on completion.
• Mechanical extract ventilation sized for the room and ducted to outside, which is a building regulations requirement and the single best defence against mould.
• Set out the tiling from the sightlines that matter, not from the corner that happens to be nearest the door.
• Silicone, seals and finishing done last and done slowly, because every one of them is a future leak if rushed.

Waterproofing, ventilation and electrics

Three regulations do most of the work in a bathroom, and it is worth knowing what they require of whoever you hire. Electrical work in a bathroom is notifiable under Part P of the building regulations: it must be carried out to the zoning rules and certified, and a certificate should be handed to you at the end. Ventilation falls under Part F, which means mechanical extract ducted to the outside air, not a fan venting into a loft void. Drainage and waste falls come under Part H.

Tanking is not a regulation, it is simply what competent practice looks like. Tiles and grout are not waterproof. In a shower enclosure or a wet room the waterproofing is the membrane behind them, and in a wet room it also has to be continuous across the floor and up the walls, with the floor formed to fall towards the drain. On an upstairs wet room in a period property that usually means the joists are notched or a former is set between them, which is exactly where a structural opinion matters.

What bathroom fitting costs in London

Bathrooms are labour heavy for their size. Labour is typically 45 to 60 per cent of the total, at London day rates of around £220 to £350 and higher for specialists, which is why a small room can cost more than a large bedroom's worth of decorating.

Bathroom tier	What you get	London cost
Budget	Standard suite, ceramic tiling, like-for-like layout	£5,500 to £8,000
Mid-range	Quality suite, porcelain tiling, new layout, heated rail	£7,500 to £12,000
High-end	Premium suite, natural stone, wet room, underfloor heating	£12,000 to £20,000+

Indicative London ranges, MyBuilder and Checkatrade, 2026.

A full London bathroom renovation sits at roughly £7,500 to £15,000 across the market. The line-by-line breakdown, including where a budget genuinely can be trimmed and where trimming it costs more later, is in our London bathroom renovation cost guide.

Small bathrooms, wet rooms and en-suites

Most London bathrooms are small, and a great many are the original box room or the back addition of a Victorian terrace. Small does not have to mean compromised. Wall-hung sanitaryware frees the floor and makes the room read larger, a walk-in shower with a low profile tray uses less space than a bath and screen, and a single large format tile makes a small room look bigger than a mosaic will. Where the ceiling slopes under a roof, the fittings have to be planned around the head height rather than fitted where they fit on a plan.

Second bathrooms are the other common request. An en-suite carved out of a bedroom, or a shower room in a loft, both raise the same three questions: can the waste reach the existing stack at an acceptable fall, will the water pressure serve two showers, and can the floor take the load. Those are answerable on a survey, and we would rather answer them before you order anything. For wet rooms specifically, our wet room guide covers the tanking, falls and drainage in detail, and the small bathroom ideas guide covers the layout tricks that actually work in a London floorplan.