Tiling and shower tray install

11 Oct 2017
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United Kingdom
I have ripped out all fittings and have an uneven/lose wooden boareded floor. The walls are part plaster board and part brick/plaster.
What is the best way of doing the following;
Prep the walls for tiling, should I replace all plaster board where I have damaged removing the old shower or simply patch and repair. Does the paint need to be removed to ensure a good bond with tiling adhesive

Secondly, how is it best to prepare the floor for tiling and a new shower tray, what is the best way of getting the floor level. The original shower tray was fixed to 3x4 but I dont want such a high lip on the shower and would like to put in a lower profile shower tray. If i overlay the whole floor with 18mm ply how do I get this level and the floor has a different heights.

Any help would be most appreciated


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Some pictures would help.

Pva the walls prior to tiling.

How uneven is the floor, 18mm ply will even it out and bridge small differences in height.
The floor doesn't look bad from your pictures. How far out is it? A pic with flat edge over worst bits may help. If you overboard the floor be mindful of the door height and levels to the landing outside.

For your stud wall I would use "no more ply" mechanically fixed and joints taped/tanked.
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Maybe it's not as uneven as I thought! Just old boards. It's an ensuite if I lay nmp I will end up with a lip into the bedroom. Can I avoid this? Bedroom been stripped and redone at same time with laminate floor, which I might replicate into bathroom instead of tiles. What about laying the shower tray. Also the rectangle tray is going to fit along the back wall in first pics. My wife wants two solid walls either side and just a door. My feelings are to create a false wall on right hand side where mixer shower will be. What's the best way to do that? Sorry lots of questions
What flooring are you putting down, tiles?
If tiles you'll need to overboard.

The no more ply is for the walls. Normal ply is fine for floor.

The shower tray instructions will tell you how to fix it down. Some say silicone, some say mortar. I will often cut or fit the tray into the wall slightly so that tiles sit over the top to prevent too much flex and give a good seal

Where is the stud wall going to be?
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The stud wall will be at the right hand side of this picture the tray will be laid right to left across the back wall where the current pipes are. Is there any issue with doing that?
If you tile over PVA and even a small amount of water gets behind it you'll be in a wold of pain...
Don’t use pva for anything... Walls don’t use no-more -ply use Wedi, Jackoboard etc. No need to tank it, just tape joints and screws. For floor don’t use ply, use 6mm no-more-ply or 6mm Hardi backer board
On mine I took the floor boards up where the shower tray was going. Fitted timber on the sides of the joists to level them up then fitted 18mm ply. On top of that I added 6mm no-more-ply.
I also built a stud wall out of 3x2 cls to hide all the pipe work and reduce the room to fit the shower tray.
The flooring was lvt which I also put 6mm no-more-ply down under it.


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