A bit of a dilemma help please

[tilerwiler]

Hi everyone Im new to this site and have done a bit of tiling before but Im stuck here.

I have been tiling my bathroom for my folks and upon taking the tiles off the wall behind its was very wet like damp with a bit of mould ( its a solid wall like block with skim) and I also noticed that some of the tiles when I knocked on em sounded hollow, now my tiling course told me that its the tiles "boasting"? Anyways the tiles are off an the wall has thankfully dried out but now the lower part (that was wet) is all dusty as in the plaster is rub off in your hands?

Which leads me to my next question, how do I seal the wall and what with, before you say yes I have read the threads about tanking, and not using PVA but I noticed no one has mentioned you can get a "waterprrof PVA" now would this solve that pva problem?

I need help asap as we have no shower atm and only a bath so help would be mucho appreciated

Thanks for helping me

 

[DHTiling]

Hello and welcome...

You will have to remove this damaged area.. it's integral strength is now knackered because of the wetting... Never! use PVA..

You can either patch in with Fast setting one coat plaster or plasterboard if the depth is deep enough.

 

[djg]

Hi and :welcome:

Waterproof or not, PVA is a no no. A chap called sWe wrote some excellent articles a while back, one of which (Cement, Gypsum, Anhydrite, Ettringite Crystals, and PVA; A Discourse) explains why.

If you're interested, take a look at sWe's guides

 

[tilerwiler]

Thanks you guys, went and got myself the tanking kit, sealed it best I can and put 2 coats on so might aswell put a 3rd on ah well its 4am maybe get some sleep lol thanks lads

 

[White Room]

What have replaced where you removed the existing plaster.

 

[kilty55]

Thanks you guys, went and got myself the tanking kit, sealed it best I can and put 2 coats on so might aswell put a 3rd on ah well its 4am maybe get some sleep lol thanks lads

hi ,dont put 3 coats on unless it states it imo and did you remove the old damaged plaster and what did you rerplace with?