People sometimes ask why a wetroom costs more than a regular bathroom of the same size. The honest answer: because the floor and the walls have to become a single watertight membrane before any tile lands on them. Everything you see when the job is finished — the linear drain, the seamless wall, the shower head tucked into a niche — sits on top of an invisible layer that's doing the actual work.
Here is what we mean when we say "properly tanked", and why it matters.
The tank-out itself
The whole shower zone — floor, walls, often the surrounding floor too — gets a waterproof membrane applied directly to the prepared substrate. We use a certified system, not a roll of pond liner and hope. Membranes come in liquid-applied and sheet-applied forms; we pick whichever is right for the substrate and the geometry of the room.
Corners and floor-wall junctions get extra: bandages or pre-formed inside corners that bridge the joint and stay flexible if the floor moves a fraction over the years. Pipe penetrations and waste outlets get their own gaskets. Every overlap and every edge gets the right product, and the whole thing is checked before any tile adhesive touches it.
Falls planned on paper
Water has to go somewhere. A wetroom floor needs a fall — a slope toward the drain — that's gentle enough to walk on but steep enough that a puddle never forms. We work this out on paper before the floor goes down: where the drain sits, where the high points are, what the room's existing levels can take.
Linear drains let you slope the floor in one direction, which is kinder to large-format tiles. Centre-point drains need a four-way fall, which means smaller tiles. Both work — they're different design choices that get made on day one and shouldn't get reversed at the end.
Drains that earn their place
The drain isn't just a hole in the floor. It's a stainless-steel-bodied channel with a removable cover, a clamping flange that mates with the membrane, and a trap that catches hair. Linear drains can run flush with the wall (cleaner sight-line) or sit a few centimetres in (easier tiling around). We pick the unit and the position before tile orders get placed, because changing it later means lifting the floor.
Low-threshold and level-access designs
If you're building a wetroom for accessibility — a bungalow conversion, a future-proofing job — the threshold matters as much as the membrane. We can design the wetroom to be true level-access, with the bathroom floor and the wetroom floor flowing as one surface. That requires deeper-than-normal joists or a routed-down screed, plus careful work at the doorway. Worth doing properly the first time.
What cheap quotes usually skip
If a wetroom quote is suspiciously cheap, ask:
- Are the walls being tanked, or just the floor?
- What membrane system are they using, and is it certified for wet zones?
- Are corners being bandaged, or just sealed with the same membrane?
- Is the drain unit being supplied, or is the customer expected to source it?
- What's the thickness of the screed beneath the tiles?
The honest cheap answer is usually "we're tanking the floor with a paint-on, not the walls, and there's no bandage at the corners." That works for a year or two. It doesn't work for ten.
The bit you actually see
Once all of the above is in place, the wetroom can be as plain or as theatrical as the room calls for: a single bench in dark slate, a backlit niche running floor-to-ceiling, brushed brass thermostat valves, a mosaic accent wall behind the shower head. The materials get to be the show because the structure underneath is doing its job silently.
Got a wetroom in mind for Hull, Hessle or East Yorkshire? Get in touch — we'll come and look at the room before quoting.