In short: A wet room is a fully tanked room where the whole floor is waterproofed and laid to a fall, with no shower tray. A walk-in shower uses a low-profile or flush tray with a fixed screen. Wet rooms give true level access and suit small rooms and accessibility needs; walk-in showers are quicker, cheaper and suit most standard family bathrooms.
What's in this guide 7 sections
01 What is a wet room?
A wet room is defined as a fully tanked bathroom where the entire floor is waterproofed and laid to a fall, draining to a central or linear gully, with no raised shower tray and no step to cross. The waterproofing — not the tiling — is what you are actually buying.
Creating one means lifting the floor, installing a former or forming falls in the screed, fitting the drain and its trap, applying a tanking membrane across the floor and up the walls, and only then tiling. In a timber-floored property the joists usually need a former dropped between them, which is why a wet room takes longer and costs more than a standard bathroom.
02 What is a walk-in shower?
A walk-in shower is an open shower area using a low-profile or flush-fitted tray with a fixed glass screen and no door. The tray contains the water, so the rest of the floor does not need tanking or forming to a fall.
It is the more common of the two by a wide margin, because it gives most of the visual openness of a wet room with a fraction of the floor work. A flush-fitted tray gets you close to level access without the full build-up a true wet room needs.
03 Wet room vs walk-in shower: the differences that matter
| Wet room | Walk-in shower | |
|---|---|---|
| Shower tray | None — the floor is the tray | Low-profile or flush-fitted tray |
| Level access | Yes, genuinely step-free | Low threshold, not fully level |
| Waterproofing | Whole floor and walls tanked | Shower zone walls tanked only |
| Floor works | Floor lifted, falls formed | Minimal — tray sits on prepared floor |
| Typical install time | 10–15 working days | 4–7 working days as a standalone job |
| Relative cost | Higher | Lower |
| Best for | Small rooms, accessibility, bungalows | Standard family bathrooms |
| Risk if done badly | Water reaching the structure | Leaks at the tray edge |
04 Which one should you choose?
The honest answer depends on three things, in this order.
- Do you need genuine level access, now or within ten years? If yes, choose a wet room. Nothing else gives you a floor a wheeled frame or a wheelchair can cross.
- How big is the room? In a very small bathroom a wet room can be the more sensible choice, because losing the tray footprint gains you usable space. In a room of normal size, a walk-in shower usually wins.
- What is the floor construction? A ground-floor or concrete-floored room takes a wet room easily. An upstairs room with shallow Victorian or 1930s joists sometimes cannot achieve true level access without a raised, ramped threshold — a good fitter will tell you that at survey, not after starting.
05 Will a wet room make the whole bathroom wet?
A correctly designed wet room keeps water in the shower zone through the fall of the floor and a glass screen, so the rest of the room stays usable. Some spray is normal, which is exactly why every surface is tanked and why the WC and any joinery are positioned away from the wet zone.
Ventilation matters more in a wet room than in any other type of bathroom. A larger area of the room gets wet, so it needs proper mechanical extraction with an overrun, not a token fan.
06 What goes wrong, and why
Almost every wet room failure traces back to waterproofing rather than wear. The membrane is buried under the tiling forever, so it is the part of the job most often skimped by a cheap quote and the part you cannot inspect afterwards.
- Partial tanking — the floor done but not the wall junctions, so water tracks sideways.
- The drain not sealed into the membrane, which puts a hole in the waterproof layer at the wettest point.
- Falls too shallow or falling the wrong way, so water sits rather than drains.
- Movement joints grouted rigid rather than siliconed, so the grout cracks within a year.
- Tiles bedded directly onto floorboards with no backer board or decoupling — timber moves, tile does not.
If you are comparing quotes, ask each one specifically what tanking system they will use and how far up the walls it goes. The answers vary enormously, and the price difference between quotes usually lives right here.
07 Do you need planning permission or building regulations approval?
You do not need planning permission to convert an existing bathroom into a wet room or walk-in shower, because it is an internal alteration that does not change the external appearance of the property.
Building regulations can apply where you are creating a bathroom in a room that was not one before, altering drainage, or adding new electrical circuits. Ventilation requirements apply in both cases. Any competent fitter will tell you at quote stage which of those your project triggers.