I am about to do my first wet-room/area, I have an new build en-suite which has a raised floor with a 1800x900 area sunken by 100mm. Builder has floored totally in 18mm ply (on raised suspended floor joists), but has left it lightly screwed so it can be changed if necessary. Walls are skimmed plasterboard (which I would not have again, given the weight restriction). I plan to use tanking membrane on walls into a former. Given the support already in place and flexibility on depths what would the most logical product be in this instance?
Input gratefully received.........
Input gratefully received.........