Making a wall waterproof

[iffy100]

Not sure if this is the right section but here goes.

I have a modern built house in which the tiles around the bath where only tiled half way up. This means that water is hitting the exposed part of the wall and causing damage. Im thinking of removing the small section of the plasterboard that is damaged and patch repairing it in view to make the exposed part 'waterproof'.
My question is - will three coats of PVA and then paint make the wall waterproof? If not is there another idea anyone can suggest?

 

[Grenage]

I believe what you're looking for is something called aquapanel.

 

[iffy100]

good idea but rather expensive.

 

[Grenage]

I would wholeheartedly recommend not taking the PVA/paint approach. Not only will the paint not stick to the PVA, but I'm pretty sure PVA can reactivate when wet.

 

[Snacker]

I would wholeheartedly recommend not taking the PVA/paint approach. Not only will the paint not stick to the PVA, but I'm pretty sure PVA can reactivate when wet.

+1

Can you not get hold of some matching tiles and add another few courses as necessary to bring the level of the tiles above the level that the water gets to?

 

[iffy100]

No snacker wouldn't resolve the issue. The issue is that the tiles are not high enough up the wall. The flats where made on a right budget.

 

[Snacker]

No snacker wouldn't resolve the issue. The issue is that the tiles are not high enough up the wall. The flats where made on a right budget.

I'm confused I may well be missing something, but I'm saying that if for example you've got your bath, then 4 courses of tiles on the walls, you could add another 2, 3, 4 or whatever courses above them to increase the height of the tiled area.

Forgive these numpty diagrams but hopefully they show what I'm on about. In one you have your bath and then two courses of tiles above it. In the other one you've got your bath, the original two courses of tiles and another two that you've added:

______
______
______ ______
______ ______
______ ______
(BATH) (BATH)


I had to do this at an old house and as long as you can get hold of matching tiles it's a simple job.

 

[iffy100]

Sorry Snacker, I wasn't clear on the scenario as I was looking for a specific answer on the question. Any ow, please let me clear things up.
I have actually tiled the bathroom as per your diagram but the problem is that the materials used by the bulinding company are not the right materials. There is far too much flex in the plasterboard and the tiles move causing breakage/splitting.

There is really no other method I can see that will make the bathroom look nice apart from the idea I had.

 

[blightymam]

I would wholeheartedly recommend not taking the PVA/paint approach. Not only will the paint not stick to the PVA, but I'm pretty sure PVA can reactivate when wet.

Agreed.

If you go ahead with your idea Iffy, you may just make it all look a lot worse. Have a look at this - excellent info!

//www.diynot.com/diy/threads/mist-coat-or-pva-bare-surface-basics.425261/

If the plasterboard is moving and causing the tiles to move and break, the only way of doing this is to start again. If the foundations are rubbish, the result will be too and there really isn't an easy solution.

I am also a bit confused, in your original post you say the wall is tile half way up and you have exposed paint. Then to Snackers idea you say that you have tiled his way, yet you have wall still getting wet. Surely that means you have not tiled high enough to stop any wall getting wet and you have not done what he suggested? So..tile higher perhaps until you have covered every part of the wall that gets wet?

 

[Snacker]

If the plasterboard is so thin and flexible that your tiles/joints are cracking then I can understand why adding more courses of tiles would be pointless.
They should have used at least 12.5mm board to tile onto but it sounds like this isn't the case.

Ok, another possible option then. Maybe you could use this to waterproof the wall:

http://www.zinsseruk.com/product/watertite/

It says that it dries to a smooth, white finish but I don't know if it's more satin or matte. You'd also need to find out if you can overpaint it (unless you already have white walls). It does say it can be tinted but I'd imagine that even if you couldn't emulsion over it straight away, you'd at least be able to prime it using one of their other products, and then overpaint it.
One thing I'm not sure of is the lifespan of the emulsion overpaint if it's regularly exposed to a lot of water though. I'd definitely use bathroom-specific paint to give it half a chance as based on past experience it copes with water surprisingly well. In fact at that other house I mentioned where I had the same problem with the tiles being too low I used bathroom paint as a quick fix and it ended up being close to 6 years before I finally got round to adding the additional tiles, during which time it had a daily splashing from the shower, and it was still pretty much intact.

 

[WalksWithTurkeys]

I wonder if Zinsser Gardz would do the trick? I applied it to bare walls where I was unable to remove the wallpaper paste (too much soaked in). It is an acrylic sealant. The only issue is that you will need to apply at least one more top coat than normal, because Gardz seems to reduce coverage for the first coat. I applied 4 coats of paint over it!

I would recommend something like an acrylic paint for the top coats, which being impremeable should resist damp far better than normal paint.