Wall Tiles on painted wall?

[SproutsDad]

Your advice please on preparing a wall for tiling with 30cm x 60cm x 8.5mm cement based tiles going floor to ceiling in a shower & washing utility room. The room is newly plastered done 6 months ago, most on solid wall, some on studwork. Adhesive would also be a powder mix cement based

Our original plan was to only tile in the shower cubicle area, so the surrounding wall was given a mist + 2 coats of a non-vinyl contract emulsion, plain easily sandable white.

I now want to tile the whole wall, including the newly painted part, done about 3 months ago.
As these are quite heavy tiles (I haven't bought them yet), how do I prepare the wall to take them? Does the emulsion paint have to be taken off/ sanded back? It is very dry and sound, the plaster underneath was just a skim, on very old walls. Or is there a primer/stabiliser etc. that will help?

Your advice please before I proceed along the wrong route or ditch it when there may be a straightforward solution.

All help much appreciated.
Thanks

 

[bobasd]

dont tile on plasterboard in wet areas like the shower enclosure or over the ath.use backer board.
dont worry about going over the paint. lightly sand it and then use powdered adhesive you mentiondont use the stuff in tubs.

 

[SproutsDad]

Bobasd, sory for such a delayed response. Thanks, you say ......

dont tile on plasterboard in wet areas like the shower enclosure or over the ath.use backer board.

>> I have replaced plasterboard with 12.5mm backer board and used special 'gold' Wickes screws.
Can I tile with powder mix adhesive directly on to the board, or would a primer be best? - Bal acrylic primer or Mapei?

dont worry about going over the paint. lightly sand it and then use powdered adhesive.

>> Likewise should I prime it after sanding the paint?

Thanks

 

[bobasd]

no need for priming on backer board or p/board.just set out your lines and tile away.