Tiling a bathroom

[karenanne1]

Dear forum,
I'm getting my bathroom changed, the new plaster board is upon the walls and the tiler is sticking the tiles directly on to plasterboard with out any skim of plaster, is this the usual route ? I'm concerned regarding a shower that will be over a bath and new leakage.

 

[Goldberg]

There's no point in skimming before tiling.

However, if any of the tiling is in a shower area, I would tank the plasterboard first.