Sealing a shower cubicle

29 Nov 2008
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United Kingdom
Sorry if this has been asked a million times.

I have installed a walk in shower cubicle (3 walls and a sliding door).

When I installed the tray, I sealed it with masses of sealant between the wall and the tray, then tiled down to the tray and sealed the joint.

As far as I can tell, I can't see anywhere for the water to ingress at the tray/wall joint it seems pretty well sealed.

Water is getting in behind this joint and appearing as moisture on a grouted joint on the outside of the shower. Where the outer corner of the tray meets the wall if that makes sense. It seems as though the water is getting trapped between the two seals and finding its way to this corner !

Is it possible that it is seeping through the grout ? I had to space out the bottom joints, due to me being a crap tiler !!!! So they are about 4 - 5mm !!

Also, should all the corners be sealed top to bottom in a shower ? Regardless of the type of tiles used ?
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Very possible. water proof grout just means it doesnt fall apart when in contact with water - it still absorbs water and allows an amount to pass through it.
How did you seal the door,inside,outside.
Shower doors are sealed outside only this allows any water to run back into the tray.
Inside AND outside !!!! I think this could be the problem !!!! Thanks, I will check it out !!!
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Another thing a lot of people miss is that the tray to tile joint should be sealed before fitting enclosure, not necessarily the whole lot, just where the wall profiles sit.

As mentioned, a shower should be sealed right down both wall profiles and bottom profile on the OUTSIDE and I often seal both wall channels on the inside also but the bottom profile should be left unsealed on the inside.

If in doubt, take a look at the Showerlux Installation instructions for one of their generic screens
I worked for a shower manufacturer for 10 years, incorrect application of silicone sealant is the single biggest cause of leaks. The advice you have been given is broadly correct.

Always fully seal the shower tray to the tiles before installation and allow it to cure for at least 24 hours before installing the shower enclosure. Failure to do so will allow water to leak under the base of the wall profiles and into the walls. Seal the wall profiles to the walls on the inside and outside of the shower enclosure. Finally seal the shower enclosure to the shower tray on the outside only. Always apply silicone sealant in one go, do not part seal and then join with further sealant after it has cured as it will often not adhere correctly.

Even when sealant is applied correctly problems can arise if the shower tray settles or flexes when weight is applied. The silicone can pull away from the shower tray allowing water to escape. The subject is covered with pictures on this web site

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