Tanking corners on skimmed walls

Hi all -

I'm about to give my downstairs showerroom a makeover and have a question about tanking. There seems to be all sorts of info and systems out there, but essentially what is there now are plastered walls and a cement floor that has been painted with that waterproofing paint then tiled over. There's a shower unit but no tray, but the floor slopes to a drain. It's been working fine, but is just dated.

I want to remove the tiles and change the shower unit; it'll be completely sectioning off that end of the bathroom as it'll be a sliding door glass panel. But from what I've read because there's no shower tray its technically not a 'showerroom' but a 'wetroom' and therefore i need to tape all the corners of the walls.

I really just want to know what the purpose of taping up the corners is, when there is no actual joint there. I get it when I've put some sort of board up that has joints, but if the whole wall is skimmed and i'll be protecting it with the tanking paint anyway, I don't quite get it.

Can anyone else help with this?

Thanks!

Dylan,
Wall boards move/expand/shrink.
This can/will lead to small cracks, typically in corners of walls (eg wall to wall, wall to ceiling, wall to floor.
Not normally an issue in a bedroom etc and small so not normally seeing (or covered by coving).

But in a wet room where the paint provides the waterproofing this small crack can be disastrous.

So lengths of fibreglass mesh can be applied into the corners (placed onto wet waterproofing material, left to dry and then painted ontop.
The mesh is semi flexible so can keep any cracks sealed.

SFK

SFK said:

Dylan,
Wall boards move/expand/shrink.
This can/will lead to small cracks, typically in corners of walls (eg wall to wall, wall to ceiling, wall to floor.
Not normally an issue in a bedroom etc and small so not normally seeing (or covered by coving).

But in a wet room where the paint provides the waterproofing this small crack can be disastrous.

So lengths of fibreglass mesh can be applied into the corners (placed onto wet waterproofing material, left to dry and then painted ontop.
The mesh is semi flexible so can keep any cracks sealed.

SFK

Click to expand...

Thanks so much mate. In my case I don't have boards, just plastered concrete walls and a concrete floor, but I'm assuming it still applies?

Dylan,
Possibly / Probably / Cannot tell.
Even concrete expands and shrinks, and perhaps at different rate to the plaster. So cracks can and will form.
So for a bit of extra tape and time it is a good idea if you have any concerns.
And water does get through the smallest of cracks.

Just the tape is available on eBay and not that expensive.
https://www.ebay.co.uk/sch/i.html?_...m570.l1313&_nkw=Shower+Waterproofing&_sacat=0
SFK

You can get a good tanking kit from tiling wholesalers.Bob