You could lay under floor heating under the wet room flooring, which is usually made from a rubber/vinyl/polymer material.
A rubber flooring will offer the best "natural’ warmth, in fact you shouldn’t need under floor heating with a rubber flooring.
Or you could lay non slip ceramic or porcelain tiles with under floor heating.
If tiling ALWAYS lay 8mm marine ply between the existing floorboards and your tiles, no need to do this if using vinyl wet room flooring.
A decent installer should be able to answer your queries.
ALWAYS get it installed by a professional wet room installer.
I used to instal bathrooms & shower rooms, but if someone wanted a full on wet room I usually contracted it out, even the slightest error can have devastating results.
If you get a plumber to instal it, ask for references from customers who’ve had a wet room fitted.
You’ll probably find countless plumbers or bathroom installers willing to accept the job, but you really need someone who ONLY specialises in wet rooms.
My father lives in a council house and the council installed a disabled wet room 18 months, in fairness it looked basic but ok, however 18 months on he’s now having to get the council to replace the kitchen ceiling due to the wet room floor above leaking.
Basically a plumber is not the same as a wet room installer
Theres lots of info online.
I’ve seen this companies work, and they are probably amongst the top end installers in the UK.
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