Tiling painted render?

[Miles]

Going to put up tiles in the kitchen ... part of the surface is painted plaster, not sure what type of paint, house built in 1944. Do I need to remove the painted plaster (and level with gypsum mortar) or can I prime and tile on?

 

[kimpo]

If the plaster is attached, it's fine... Otherwise, a piece of advice is to glue a plasterboard/rotgips board and then tile on that. You could also do as you mentioned and knock down the plaster, but it feels a bit "overkill" when it's just a bit of kitchen tiles.

Good luck!

 

[Miles]

Okay, well it stays there pretty well thanks to the color but it's that kind of plaster that "crumbles away" if you start digging into it a bit :-/
Is a primer needed on the color then?
Gipsskiva is unfortunately not an option as it would then build too much over the edge of the sink.
Cheers!