Sealing a wide gap on one side of a shower tray

[Haymish Pupkin]

Hi All

I need to seal a shower tray but the tray is 0.5"-1" away from the wall at the back (the wall facing you as you walk into the cubicle). I have filled the hole with plumbers mate putty and now I'm not sure what to do next.

I could fit a long thin strip of WBP ply over the gap along the length of the back wall so that it over hangs across the tray by half an inch or so, then I could seal / stick it to the walls / the shower tray with no more nails or silicone or something where the ply meets the tray, then tile over the ply and seal with grout. Does that make sense? I assume nothing will stick to the putty I have used. Would someone walk me through the process of what I should do / not do to seal a gap like this?

Thanks

Haymish

[Lobster]

What's the overal status here - is this an existing tiled shower in which you're trying to repair a hole, or a completely new installation?

IMHO flat areas within showers are to be avoided like the plague; yes they can be sealed but they are inevitably the first place to leak.

*If* it's a new install, I'd be looking at battening out the wall and applying aquapanel board to that, then tiling the aquapanel so the tiles can be sealed directly to the shower tray, thereby eliminating the flat strip.

David

[Christian McArdle]

Should be fine. Plan the tiling so that you don't rely on sealant/grout for the majority of the sealing. Basically put the "horizontal" tiles down first and then tile down the wall to them, so that water running down the wall hits the horizontal surface. Obviously, you want a good fall to the horizontal surface. 45 degrees is good. ;-)

Also, I'd use some screws in there. I'd cut some triangular brackets from some pine, screw these to the wall and screw the WBP to these.

Christian.

[Haymish Pupkin]

Hi David

The shower cubicle has been in place for a good long time and it seems rock solid apart from this issue. There are tiles on the walls so if I put a piece of wood over the gap if would have tiles to the rear and sides, putty below oh and bit of the shower tray and nothing in front of it.

Help

[Haymish Pupkin]

Thanks Christian

Sorry, I should have stated that the shower subicle is already installed and has tiles in place already. The problem is that whom ever installed it didn't do a great job with their tape measure so I'm left with this gap to re-seal when in fails every year. If I put some WBP ply in there it will have tiles to the left, right and rear and putty / shower tray below it so I'm not sure if it's a good idea or how to secure it in place.

[Christian McArdle]

Remove the lowest row of tiles on the problem wall. Screw the triangular wooden brackets below this, with enough gap to the row above for the ply and tiling. Tile the ply fillet, so that the tile surfaces go underneath the protruding tiles of the row above. Seal and grout. If the fillet is too narrow to need tiling, use a uPVC profile instead and seal to the tray and wall with silicone, ensuring that the profile ticks up behind the wall tiling.

Christian.

[John]

I had a similar problem with a shower tray that didn't fit a shower cubicle. In my case the gap was about 3" all round. To add to the problem, the floor joists underneath were old and flexed. (The house was nearly 300 years old and replacing them wasn't a realistic option). The previous owners had built a wooden frame around the shower try and tiled onto that. The tiles had cracked as everything flexed. That let water onto the wood which eventually rotted making matters worse. I ended up filling the gap with expanding foam, cutting the top to a slight fall and tiled on top of that. In order to maintain flexibility, I grouted the tiles with silicone. I used 4" tiles cut to overlap the shower tray by about 1/2". If the tiles didn't seal, the foam provided a secondary seal. After 6 years, the structure was still perfect.

John

[The Natural Philosopher]

Top marks for a practical solution to an otherwise almost insoluble (haha) problem.