Hi All

I have decided to tackle my bathroom as my first tiling project and am in need of some help.
I have started taking off the old tiles and the top coat of plaster is coming off with them in most places. I know from what I have read on this forum that there are some plaster base coats that you can tile onto and some that you can't, the problem I have is that I don't know what type mine is. The plaster under the top coat seems to be very hard and isn't easily scratched or marked, the house is a 1960's semi.
The pictures show one of the walls where the plaster has come away.
Any advice would be very much appreciated, I would also be grateful for any advice about which adhesive to use, I will be using 25 x 33 cm ceramic tiles.





Thanks, Dave.

Would have thought it would have been sand/cement at that age, hard to tell from the photo.

Have you tried digging an old screw driver into it and breaking up a small sample to see if there's any sand contained in it

looks like bonding to me , that wall needs re-boarding ,dot new boards with dry wall adhesive

Does look decidely pink

The finish on a sand/cement backing will leave a residue remaining if it has been applied right which could give the impression of a gypsum backing coat

I thought it looked like sand and cement, which if so, is fine to tile onto. If it's bonding best to have it skimmed, prime it once the skim has cured (with an acrylic primer, not pva!) and tile away.

Thanks for all the replies

Luckily I discovered that I have a very helpful builder across the road who is going to skim the walls for me, all except one which I am going to dot and dab with MR plasterboard as it is in a bit worse condition than the others and I have to get a bit of plumbing behind there.

My question is, what preparation do I need to do before tiling onto the plaster and the plasterboard, and what is the best adhesive and grout to use.

Thanks, Dave

most cement based adhesives will require priming before fixing onto the wall,if you are using tiles 300mm x 300mm you can use tubbed adhesive and it doesn't require priming,personally i would use mapei keraquick,but it is fast setting and could cause you probs if your not quick enough

Was it render or a gypsum undercoat

Originally Posted by whitebeam

Was it render or a gypsum undercoat

It is bonding apparently

Just a couple more questions,

I'm also tiling the floor, I'm going to screw WBP ply over the tongue and groove floor boards.
Do I need to seal or prime the ply before tiling and which adhesive and grout should I use.
I'm sure you've been asked this question hundreds of times before but I've searched the forum and haven't been able to find an answer.

Thanks

make sure floor boards are firmly fixed and flat ,some older floor boards have a slight camber in them,raipd flex adhesive & flexy grout mapei adhesive would be my choice,and yes prime the ply

Mapei would be my choice too, but check with your chosen adhesive tech dept. Most advise prime back, sides, but vary about face, depends on your adhesive choice