Water resistant plasterboard needed on cement before placing bathroom tiles?

My name is Robert and I am a tiler by trade. So you have three questions which I will tackle in order. Question 1. If your walls have been plastered with cement I would be very surprised. Sand and cement screed was last used in the 1960s. It is more likely to be bonding plaster or hardwall plaster which are usually pink or grey depending on the manufacturer. This should ideally have a skim coat prior to tiling which should be primed prior to tiling. Your builder will tell you exactly what is on the walls. Ask him, it is not a trade secret. Question 2. Plaster board NEVER goes on the floor. If your floor needs levelling, a latex levelling compound can be used. If it is susceptible to movement (new screed, wooden floor boards) then a movement membrane such as Ditra should be used. Question 3. No, you do not need to moisture proof the ceiling. If it is new plaster then a mist coat of paint should be applied prior to painting. I usually use 60% white emulsion paint to 40% water when painting any new plaster but most paint manufactures will have this information on their websites. I hope you find this information useful. Robert.

We agree with Robert's advice and would like to add the following too 1) Aquaboard can be used in the shower or bath area additional to plastering but not always necessary plaster should be sufficient 2) If existing floor is floorboards, this would need to be laid with marine ply before tiles laid If you are worried about moisture or damp we would suggest having an extractor fan fitted Hope this helps Terry Interiors by Bkb Ltd