The short answer
A wet room typically costs £5,000–£15,000 in the UK in 2026. The extra over a standard bathroom comes from full waterproof tanking of the floor and lower walls, plus a new drainage point with the correct falls. The tanking is the key cost — get it wrong and water damage follows. See the full new bathroom cost guide for how this compares.
A wet room — an open, level-access shower area where the whole floor is the shower tray — is increasingly popular for its clean look and accessibility. It is also more demanding to build than a standard bathroom, because the entire room must be waterproof rather than just the shower enclosure. This guide explains what a wet room costs, why, and what the extra spend buys you.
Wet room costs at a glance
- Typical wet room £5,000–£15,000
- Key extra Full waterproof tanking
- Drainage New point with correct falls
- Floor build-up Former / graded screed for the fall
- Best suited to Accessibility, modern open look
- Typical duration 8–14 working days
Why a wet room costs more
In a standard bathroom, only the shower enclosure and splash zones need to be fully waterproof. In a wet room, the entire floor and the lower walls are continuously exposed to water, so the whole area is tanked — coated with a waterproof membrane system before tiling — and the floor is graded to fall toward a central or linear drain. Achieving that fall usually means a proprietary shower former or a graded screed, and the drainage point has to be created and connected with the correct gradient. This combination of full tanking, floor build-up and new drainage is what separates a wet room from a normal bathroom on cost. Done properly it lasts for years; done badly it leaks into the structure below, which is why workmanship matters more here than almost anywhere in the home.
| Element | Standard bathroom | Wet room |
|---|---|---|
| Waterproofing | Shower zone only | Whole floor + lower walls |
| Floor | Level, tiled | Graded former / screed to drain |
| Drainage | Existing shower waste | New point, correct falls |
| Tiling | Walls + floor | More floor detail and cutting |
| Typical cost | £6,000–£12,000 | £5,000–£15,000 |
What the waterproofing involves
Tanking is a layered system: the substrate is prepared and primed, a waterproof membrane (liquid-applied or sheet) is installed across the floor and up the walls to a safe height, joints and pipe penetrations are sealed, and only then is the tiling applied over the top. The shower former or graded screed creates the fall to the drain. Our flooring and waterproofing guide goes into the detail. Because the membrane is hidden once tiled, you cannot judge it after the fact — which is why using a bathroom installation specialist experienced in wet rooms matters.
Where the cost lands within the range
A modest wet room on a solid ground floor, replacing an existing bathroom, sits toward the lower end. Costs rise with a suspended timber floor (which needs reinforcement and careful detailing for the fall), premium large-format or stone tiling, underfloor heating, a glass screen, and any structural or drainage complications. Upper-floor wet rooms demand particular care because a leak there damages the rooms below. Our labour cost guide covers the trades involved.
Is a wet room a good idea?
Wet rooms suit accessible, step-free bathing and a clean, contemporary look, and a second wet room can add appeal. But removing the only bath in a family home can deter buyers, and a poorly built wet room is a liability. Weigh accessibility and style against the household’s needs — our bath vs shower guide and does it add value guide help. This page is general information; the actual cost depends on your floor structure, finishes and chosen specialist.
Compare wet room quotes
Use our service to compare itemised quotes from a bathroom installation specialist experienced in wet rooms and tanking.
Frequently asked questions
How much does a wet room cost in the UK?
A wet room typically costs £5,000–£15,000 in 2026. The range reflects the floor structure, tiling, drainage and whether features such as underfloor heating are added. The full waterproof tanking is the key extra over a standard bathroom. These are typical illustrations, not quotes.
Why is a wet room more expensive than a normal bathroom?
Because the whole floor and lower walls must be waterproofed (tanked), the floor must be graded to fall toward a new drainage point, and that drainage has to be created with the correct falls — far more than the localised waterproofing a standard shower needs.
Can any bathroom be turned into a wet room?
Most can, but suspended timber upper floors need extra reinforcement and careful detailing for the fall and waterproofing, which adds cost. A specialist should assess the floor structure and drainage before quoting.
What happens if wet room waterproofing fails?
Water penetrates the structure beneath, which can cause rot, damage to ceilings below and costly remedial work. Because the tanking is hidden once tiled, it is essential the waterproofing is done correctly by an experienced specialist from the outset.
Sources & further reading
- KBSA — consumer guidance on bathroom and wet room projects
- CIPHE — plumbing and drainage standards
- GOV.UK / Building Regulations Approved Documents G and H — sanitation and drainage
- TrustMark — finding a vetted tradesperson for home improvement work
This is general information, not advice for your specific property or installation. Costs, timescales and outcomes vary with your home, floor structure and chosen specialist. Bathroom Answers is an independent information and introduction service, not an installer.