Preparing walls for tiling a shower

[RobinClay]

Hi !

I've taken out the old shower tray, and am putting in one twice the size.

I stripped off all the old tiles - and some of the skim-coat came too - AND some of the render, exposing the brickwork..

I've cut chases in the brickwork for the water pipes, and have filled the chases with spray foam topped by sand/cement render, which I've also used to replace the spalled render.

1. Should I skim this new rendering and the patches with polyfilla, or can I just leave the humble bits to be filled with grout ?

2. As the new tray is bigger, much of the walls to be tiled have previously been painted. Can I just leave this painted surface as it is, and tile over it ?

3. What primer should I use, over ALL the area to be tiled ? I have heard that I should use either BAL SPR or BAL WP1 or Ardex WPC, and Sandtex stabilising solution has also been suggested. What do YOU suggest ?

The new tiles are 200 x 250 glazed ceramic.

 

[tictic]

Hi !

I've taken out the old shower tray, and am putting in one twice the size.

I stripped off all the old tiles - and some of the skim-coat came too - AND some of the render, exposing the brickwork..

I've cut chases in the brickwork for the water pipes, and have filled the chases with spray foam topped by sand/cement render, which I've also used to replace the spalled render.

1. Should I skim this new rendering and the patches with polyfilla, or can I just leave the humble bits to be filled with grout ?

no need to skimm render.

if patches not to deep skimm it with a cement based addy.

2. As the new tray is bigger, much of the walls to be tiled have previously been painted. Can I just leave this painted surface as it is, and tile over it ?

score paint with a stanley blade.

3. What primer should I use, over ALL the area to be tiled ? I have heard that I should use either BAL SPR or BAL WP1 or Ardex WPC, and Sandtex stabilising solution has also been suggested. What do YOU suggest ?

bal primer/apd/sbr..or mapei primer G...
then a cement based addy(bagged).
The new tiles are 200 x 250 glazed ceramic.