Does a sand and cement wall need tanking?

[Stuart Williams]

I've had a search and can't find the answer probably because it's obvious but want to check anyway.

Stripped the old downstairs wet room and removed all the plaster as it was damaged back to the sand and cement coat. After leveling the floor I'll be installing a tray and screen.

My question is, I've been given tanking solution to paint on by a mate, do i actually need to paint the two walls the shower is going on? I'm tiling straight onto the sand and cement coat with a cement based adhesive and grout and a coat of SPD primer.

Best image I could find attached, you can make out the corner.

 

[hmtiling]

Definitely needs tanking. It should be waterproof before a tile touches it.

 

[Italy]

definitely tanking

 

[Italy]

Definitely needs tanking. It should be waterproof before a tile touches it.

puff, I always slow 🙁

 

[LM]

Yes same as above, it looks like a gypsum finish coat which is moisture sensitive, so it defenitly needs primed and tanked.

 

[Stuart Williams]

it looks like a gypsum finish coat

Thanks Lee. That's all been backed off, it had its day, just the sand and cement left now. I'm confident in your answers so going to tank it before installing the tray and tiling.

Thanks all

 

[Stuart Williams]

Quick update, I'm ready to start tiling. With the tanking solution is it a case of painting it straight onto the cement first then tiling on top, or do I need to do anything before tanking? I'm assuming g I don't need to SPD over the tanking before tiling. Cheers

 

[Dumbo]

Follow the instructions that come with the tanking but I expect it will say to prime the wall prior to tanking . Also I have not found a tanking kit yet that requires priming before tiling and I like to prime most substrates .