Hi i have job to do next week the walls are plaster board but have been painted.The paint is a sheen,shiny finish i'm sorry dont know size of tiles yet but will it be ok to prime with a ackrilick primer and tile straight on or will i have to takr plasterboard of first.

The paint could be vinyl silk and you will never scrape that off, depending what tile that your going to fix, weights and all that

If you have a decent sander you could sand the paint off. Gonna kick up a lot of dust, so might be less aggro to remove the plasterboard. You'll probably have a much nicer surface to tile on anyway.

Is this in a shower area

They are taking out old bathroom suit and replacing with new one i have allready advised to replace plaster board as they are taking out old suit anyway.As usual they are trying to save money wich tou cant blame them for i had read on forum that somtimes you can get away with tiling on painted surface just wanted to try and get some advise.So i am better advising them to replace board.

It depends on what the tiles will be

Will find out 2moro night.If the tiles are of a smaller nature might get away with it if not you would advise to replace board.

Yes mate, plasterboard will take 32kg tile weight, at least you know it's been done right

Cheers will explain to them tonight.

Tiles and Adhesive Weight Per Square Metre - THE TILE SOURCE

print this out and show them. Tiling on a painted surface is not a good idea. If they have kids, point out that tiles on paint can fall off, and if their kids are having a bath and a whole wall comes down onto them......

Be firm, give friendly advice and dont be afraid to walk away from the job. Good luck!