Priming before tiling

[KingTy]

Hello

I'm about to start tiling my downstairs toilet (the walls) and would be really grateful for some advice.

Do I need to prime the walls before tiling and if so do I need to use undiluted or diluted primer (I have BAL Acrylic Primer)? The surface is a mixture of mostly old plastered walls (which I've spent sodding weeks scraping all the old paint off), one plasterboarded wall that had been skimmed over in the past (the paint was a lot more difficult to scrape off here so I'm hoping I've removed enough paint from this wall to tile over) and a bit of boxing in with plasterboard.

Or should I prime some surfaces with undiluted primer and other surfaces with it diluted?

The tiles I'm using are those cheap bumpy ceramic tiles (33x25cm) with some glass mosaics for a border (I have a question about mosaics too, but I'll start a new thread for that).

I have some ready mixed Mapei Ultimate showerproof adhesive, but there's no guidance on the tub about priming walls. I'm happy to change the adhesive though (I've read mixed results about it).

Thank youl

 

[Old Mod]

BAL APD PRIMER tech sheet.

It will tell you exactly what you need to know.

I’ve not used a tubbed adhesive in 20yrs, always use bagged myself, can’t help with the Mapei adhesive I’m afraid.
I’m not 100% sure on sizes, but tubbed adhesives have a limit to the size of tile they can be used on.
I think it’s 300 x 300
I’m sure someone will correct me if I’m wrong. 😊

 

[J Sid]

I thought it was 250 x 250, but wouldn't dream of using tubed stuff

 

[Time's Ran Out]

I thought it was 250 x 250, but wouldn't dream of using tubed stuff

He’s DIY !
Most ready mixed is 30x30cm.
I always 50:50 primer.

 

[KingTy]

He’s DIY !
Most ready mixed is 30x30cm.
I always 50:50 primer.

He's a she, lol (I can't seem to change my username)

Thank you for the response. Would you recommend I use 50:50 on the plasterboard bits as well?

I don't mind getting better adhesive if people think it would work better.

 

[Time's Ran Out]

My apologies - I’am gender ignorant Tiler! Just interested in a good job.
50:50 everywhere and a powdered adhesive is best.

 

[KingTy]

My apologies - I’am gender ignorant Tiler! Just interested in a good job.
50:50 everywhere and a powdered adhesive is best.

No need to apologise, lol. And thanks very much for the advice.

I love your avatar, by the way.

 

[Time's Ran Out]

Thank you!