Sealing a shower against leaks to the room below

11 Jul 2006
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United Kingdom

I have a question about fitting and sealing a new shower. At present we have a shower upstairs in our en-suite bathroom and as far as I can see there has been a strong tendency for water to seep through the tiles and through the tongue and groove floor, through to the ceiling of the living- room. I have seen this, not just in our house, but also in a number of similar houses in the area.

I want to remove the tiles in the en-suite and replace the shower tray and start again. Are there any good tips concerning sealing the wooden floor
and shower walls against seepage to the room below, making the grout between the tiles less likely to crack and seep water or any other advice generally?

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You need to seal the shower tray, This is best done using a bathroom silicon sealer, run it around the edge of the tray before you install it, then push it in to situation, then apply more around the edge of the tray and wall.
Do this before you tile.
Are you saying you floor is floorboards which are tiled, that's totally unsuitable, floor has to be overboarded before is can be tiled as the flex in boards will dislodge tiles.
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use a good quality grout and when it dries put on a waterproofer called grout sealer or something like that , i just cant remember exactly and that should help it to not crack, and what PBD above says is spot on.

once done properly you should have no leaks, nada leako livingroomo :D
There are a couple of tried & tested ways to seal around shower trays but one thing to remember about using silicone before you tile is that nothing much will stick to it. Use it too liberally in the wrong place & it will do more harm than good; personally I would never set a shower tray in silicone. In addition, no tile sealer will prevent the grout & adhesive (even very expensive ones) from cracking if the floor isn’t properly prepared & suitable for tiling over.

This would have been better posted in the Tiling Forum but a very good start would be for you to read the Tiling Sticky & some of the many relevant Forum archive posts.
i know this is an old thread but i didnt see any mention of wether the area had or had not been tanked, possibly the water ingress is coming through the grout,running down the walls onto the floor and then through the floorboards into the ceiling

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