Grout problem - help!

[shovetheholly]

A small amount of water fell through my hall ceiling on Sunday! It came from under my bath.

Got the bath panel off and had a look. Water was dripping down the back wall behind the bath. I checked all the pipes and waste - all dry. I put the shower on, and focused it on the tiles - within a few minutes, a drip formed on the wall.

I'm pretty sure the grout is leaking (not the seal - the seal is new and fine). On examination, a line of it was cracked quite badly and felt a bit 'sandy' rather than properly dry.

So I scraped out the grout and redid it - filled the bath with water to do this. I know that grout takes a while to dry, so we decided to have baths and not shower for 48 hours. However, on emptying the cold bath and refilling this morning, I noticed the cracks had reappeared in the new grout.

I think the bath is moving a fraction when we get in/out, which is causing the new grout to crack. The wall behind is quite uneven and I suspect wasn't replastered properly before fitting, allowing some movement in the tiles.

What the hell do I do? I can move the bath upwards a little (it's on props that can be adjusted). I really, really don't want to have to take all the tiles off and redo .

You're doing all the right things to find and eliminate potential issues.

Sounds as though the tiles are loose, which is why the new grouting has cracked. I doubt the bath is moving, apart from perhaps slightly downwards when there is water/a person in it, unless the feet aren't on the floor.

Press against the tiles either side of the cracked grout. Do the ones underneath seem to 'give'? In which case they need re-fixing. They might only give when there is weight in the bath because of increased downward pressure - the seal will be flexible but the tiles under the seal shouldn't be.

It's not a big job and you can find tutorials on YouTube. I had to fix a loose tile in our old shower cubicle and it's pretty easy, providing you can get the tile out and you need to clean old adhesive off.

You may have a problem if the plaster under the tiles has blown, but in that case it needs putting right, as there's no point putting a sticking plaster on a broken leg.

Yes, there is give wowfudge - you are right, I've just tried and they are slightly loose. The plaster throughout the house needs redoing, so it could be that .

I am happy to refix them. The problem is there is new silicone seal on the bottom of them. How the hell do I get this off? It is not like the old days where you could pull it out in one long ribbon. It took me literally 2-3 hours to get the old stuff out because if kept breaking off and would only come off in tiny pieces. I can't face doing that again with the new sealant! (And I did have the right tools, too). Is there a chemical way of dissolving it?

This is a completely bodgy suggestion - but I wonder if I could just patch it up with caulk, because it's flexible?

We will need a new bathroom in the next few years, but I was hoping not to have to get it all back to plaster and redo it this soon :(

When I replaced a tile it was one of the bottom ones so the seal to the shower tray also needed replacing. If it's a new seal, it might not be a pig to get off. You can buy silicone remover, which (I've used it, but it was years ago) helps break the bond between the sealant and the tiles, but doesn't dissolve the silicone. It possibly made the job marginally easier. That kind of thing may be much improved since then.

I was expecting to find a real mess behind the tile I removed - it wasn't. I let it dry out for about a day then re-stuck the tile. Left it a day and re-grouted then re-did the sealant and left it 24 hours before using the shower again.

It might not be as bad as you think. Not sure where you are thinking of using caulk, but don't bodge it - you don't want to trap water behind the tiles and/or bring the hall ceiling down.

We were in the same situation - having a new bathroom soon so don't want to spend out on fixing the old - and we know our plaster is probably blown as it's a lathe and plaster wall.
DH came up with a brilliant bodge that has lasted 6 months so far - he just hung a shower curtain over the tiled area causing the leak!

Ha! That's brilliant! I might think about replacing the screen we have with a curtain if it continues.

Weirdly, I've had another look today and the damn tiles aren't moving any more! But when I get in the bath, especially when I put weight on the end furthest from the taps, a small crack opens up. So the problem is still there.

I read about adding latex to grout to make it more flexible - may try this next starting to get fed up with this issue so may go to the pub instead this evening!!