Pva is not suitable for tiling for various reasons and this has been debated many times here in the forum.
Sealing plaster walls before tiling.
I did question the rep about this and he was adamant that new plaster should be pva d because if not the plaster sucks the moisture from the adhesive too quickly therefore it doesn t set properly.
Before you get to it you should level the bathroom the kitchen and or the hallway walls.
Seal the walls with a skim coat and let it dry thoroughly.
Thoroughly vacuum the area and give the wall a once over with a damp sponge or cleaning cloth.
If you choose a heavier tile you will need to overboard with a backaboard.
When applying tile to a plastered surface it is important not to overload the weight of what the plaster will take before failure occurs plaster will support about 20kg m2 or about a 9mm thickness of ceramic tile.
New plaster work should be fully dried before tiling work is commenced this drying time varies upon temperatures but can take up to 4 weeks before fully cured.
Also keep the walls you are about to tile free of moisture dust and grease.
This way the adhesive will stick properly and last in the long run if you are using a good product.
If in doubt prime the walls is a general rule.
He gave me a list of their recommendations and one of them was to always use waterproof pva diluted before tiling on new plaster.
Sand with a medium grit sandpaper to create a uniform surface that s not too smooth.
Adhesive grout and tile 20kg max weight onto plaster.
Also now it s been plastered you will be restricting yourself to a tile with a max weight of about 16 kg m2.
Otherwise a few complications might occur.
You didn t say what adhesive you are going to use but one thing that is absolutely definate do not use pva.