Tiling on to uneven wall and breeze block - Tile Advice

[greenchris]

Hi, sorry, I know this is a question asked a thousand times, but I can't find a clear enough answer that matches my particular situation. I think I'm good to go, but I wanted to make sure.

Walls to be tiled are red-brick which has been plastered (and tiled) before, there's a nice skim remaining under the old tiles so will tile on to that. However, behind/under the bath was NOT tiled, so the walls are a bit uneven. I'd say the maximum difference between the wall and the plaster is probably 5mm.

Tiles are ceramic 300x600 and quite thick/heavy and I've got Mapei Adesilex P9 if that's any use. I'm quite happy to tile on to this surface but I thought I'd check with the experts.

Also see the other image, above the window. This is breeze block so will slurry prime which will make up a little of the gap. Max depth is under 10mm, so probably under 5mm after the slurry. Am I good to go?

Thanks for your help!

 

[Flintstone]

In my opinion, you need to overboard that plaster, as it looks iffy at best and the tiles will most likely be Too heavy for plaster, even perfect plaster.

 

[Perry]

They also look like concrete blocks.

 

[Bond]

Appears like a mismatch of backgrounds, patch slurry and prime, sound substrate. Then good to go.!