Before you get to it you should level the bathroom the kitchen and or the hallway walls.
Rendering walls for tiling.
Plasterboard is a very common indoor wall surface but is not suitable for tiling without waterproofing.
A tiled floor is a blessing in rooms that are exposed to water usage.
This includes kitchens bathrooms and laundry rooms.
You can tile over a wide range of surfaces and textures but wall preparation is absolutely crucial.
A reasonable level of expertise is required for rendering as it is very difficult for a first timer.
Hi firstly i am a plastering rendering amateur only hard walling up to this point.
To prepare your walls for tiling is rather simple as long as you have the right know how mindset patience and tools.
3 walls are your standard house brick and the 4th is an internal wall made of black 35mm thick air brick nasty stuff but not an option to remove.
Tiling over plasterboard involves adhering tiles to a paper surface and although this will present little problem in dry areas if the wallboard is subjected to moisture it may deteriorate causing failure.
If walls are to be painted you will need to apply another coat of top coat followed by a good sand.
If anything flick plenty of water on the area just before tiling.
For additional safety tiling rendering will waterproof your flooring and walls.
Since the tiled surface will not absorb water you need not worry about water seepage in your flooring or your walls.
If you decide to tile over the render do not pva it as all the tiles will fall off eventually see previous threads for reasons.