Converting a Bath to a Walk-In Shower: What's Involved

Swapping a bath for a walk-in shower is one of the most popular bathroom changes I get asked about, and it is usually very doable. The real work is not the tiling you see at the end. It is the drainage, the waterproofing, and the decision between a shower tray and a fully tiled floor, all of which happen before a single tile goes up. Get those right and the result is a shower that looks clean and lasts for decades. Get them wrong and you have a leak hidden inside the wall. Here is what is actually involved.

Key takeaways

• Feasibility comes down to drainage and floor depth, not the look you want.
• A low-profile tray is simpler; a fully tiled gradient floor gives the true walk-in finish.
• Waterproofing behind the tiles is non-negotiable on an open shower.
• The tiling is the easy part. The prep underneath it decides whether the job lasts.

A stone walk-in shower with twin niches in West Wickham. The seamless finish only works because the floor fall, tanking, and setting-out underneath were formed properly first. Bathroom tiling service

Is my bathroom suitable for a walk-in shower?

Before anything else, two practical questions decide whether a conversion is simple or a bigger project.

Where does the water drain?

The new shower needs a waste run that drops away with enough fall to clear properly. If your existing bath waste sits in a sensible spot and you are fitting a tray in roughly the same position, the drainage is usually straightforward. If you want the drain in a different place, or you are on a ground floor over a solid slab where there is no void to run pipework, the drainage becomes the thing that shapes the whole job. This is worth raising at the quote stage, because it is the most common reason a conversion costs more than people expect.

Is there enough floor depth?

A tiled gradient floor needs a few centimetres of build-up to form the fall and house the drain. On a suspended timber floor that is normally fine. On a solid floor it can mean the finished shower floor sits slightly higher, or a low-profile tray makes more sense. Neither is a problem, but it changes the approach.

Shower tray or fully tiled floor?

This is the real fork in the road, and it is worth understanding the difference.

A low-profile shower tray is the simpler route. It is a pre-formed, ready-graded unit that drops in, tiles run down to its edge, and you get a reliable, watertight base with less labour. For most enclosed walk-in showers this is a perfectly good choice.

A fully tiled floor means forming the whole floor to fall towards a drain, with no tray and often no upstand at all. This is what gives the continuous, seamless look and what makes a genuine wet room. It is more work because the floor has to be built up, graded to an exact fall, tanked, and then tiled to follow that fall without ponding. If you want level access or an unbroken run of floor tiles, this is the route, and it is properly a wet room at that point. For the full comparison, see wet room versus shower tray.

Why waterproofing matters more on an open shower

A bath contains its own water inside the tub. A walk-in shower does not. With no curtain, no door lip, and often no upstand, far more water hits the walls and floor and runs into the corners and the floor-to-wall joint. That is exactly why tanking is essential here and why I will not tile an open shower without it.

Tanking is a continuous waterproof membrane applied to the walls and floor before tiling, using a product such as Mapei Mapelastic, BAL Tank-it, or a Schluter Kerdi system. Tiles and grout slow water down, but they do not stop it. Behind the tiles, the membrane is what actually keeps water out of the wall and floor structure. See what is tanking for why this one layer does so much. Skip it, and the failure is invisible until the wall behind is already rotting.

What about the floor-to-wall joint?

In a walk-in shower the joint where the floor meets the wall takes constant water and constant movement, because the floor and wall move independently. That joint should be siliconed, colour matched to the grout, not grouted solid. A rigid grout line there cracks within a year and lets water through. It is a small detail that separates a job built to last from one built to look finished on handover day.

Does the tiling change once the prep is done?

Once the drainage, the fall, and the tanking are right, the tiling itself is the most forgiving part. You still want proper setting-out so the cuts fall sensibly and the floor tiles follow the fall without lipping, but the hard engineering is already done. If you are using large-format wall tiles or a natural stone, the substrate prep matters even more, because those tiles are less forgiving of an uneven background. For an accessible, level-access finish, a fully tiled wet-room floor is also the most age-friendly choice you can make in a bathroom.

Planning your conversion

A bath-to-shower conversion is a great change when it is done properly, and a slow disaster when the prep is skipped to hit a cheap price. The questions that actually decide the job, drainage, floor depth, tray versus tiled floor, and tanking, are the ones a cheap quote stays quiet about. Always get the specification in writing so you know what is included.

I carry out bath-to-shower and wet-room conversions across Bromley, Beckenham, West Wickham, Chislehurst, and Orpington, with the waterproofing and falls formed properly and a workmanship guarantee behind the work. If you are weighing up a conversion, get in touch and I will look at your room, tell you honestly what it allows, and give you a properly detailed quote.

See: walk-in shower versus bath | wet room versus shower tray | what is tanking