Bath movement causes tile grout to crack?

[Hodder]

Hi

I'm wondering if there's a reliable fix for some problem tiles.

I moved into a renovated property - new bath/shower, all four walls freshly tiled.

After a couple of weeks, the grout in the line of tiles along the side of the bath/shower begins to crack, exposing the wall behind. A large horizontal crack runs the length of 8 or so tiles. There are no (visible) problems with any other tiles.

I remove and replace the cracked grout. In some places the empty join is about 4 mm, in others just 2 mm. Not a completely straight tile line, then.

A week later, the grout starts to crack again.

I'm wondering if the problem tiles have been attached to the bath instead of the wall. The pressure of feet in the bath (which acts as a shower tray) causes movement, which causes the grout to crack. As mentioned, there's no sign of grout cracking around any other tiles. Just the ones along the bath.

The problem tiles also sound hollow when you tap them.

I'm wondering what the next step is to prevent water getting into the cracks, seeing that regrouting didn't work.

Thanks for any suggestions.

H

 

[Static]

Did you fill the bath with water before you grouted the tiles? Also is it a cheap plastic B&Q bath?

 

[diywhizz]

Like the guy says above, you should dig out all the grout , fill the bath with water and put in a flexible filler along the line of the bath to the bottom of the tiles.

 

[Hodder]

Thanks for the replies folks.

I suspect the bath is a cheapo.

Didn't fill the bath with water as I thought this only applied when working with sealant not grout.

The sealant along the bath (between the bath and the bottom edge of the tiles) is fine (no cracks).

It's the upper edge of the first line of bath tiles that's showing all the stress cracks.

Cheers, H.

 

[simon_t]

If the tiles have become attached to the bath as you suspect then when you fill the bath they will be pulled down so it might be worth trying to fill it then re-grout.

I did read about a bodge on blown plaster where dilute PVA can re injected behind plaster\tiles to help key them to the wall. It's a bit of a bodge but shouldn't do any harm if it doesn't work. Well I'm saying that, but I won't guarantee that statement.

 

[big-all]

surely if several tiles are moving in unison theres a fair chance the tiles and plaster behind is loose and no end off filling will help as eventualy the tiles will part company from the wall and finnish in the bath!!!!!!

 

[RigidRaider]

Sounds like the silicon sealant has grabbed the bottom row of tiles, which have come off as the bath settled. I would remove the lot, clean off the old adhesive and grout, take out the bath, check that the middle is on a good firm base of thick plywood then jack up the legs a bit. Replace the tiles nice and secure then as above, fill bath and seal. Then a couple of weeks later I'd jack the legs up again and fix the adjusters with some Loctite. A bit of a drag but if the tiles are off you're going to be doing most of that anyway.

Must admit that having done our shower with Mermaid boards I will never tile a bath or shower ever again.

 

[gcol]

lol

 

[Moz]

as RigidRaider says it needs refitting proper ....a Bank Holiday weekeners coming up isnt it ?

 

[gcol]

Take off the loose tiles and refit them and grout. Then when the tiles are set, fill the bath and silicone around it. Your grout cannot and will not pull the tiles away from the wall if they're stuck properly.

 

[Moz]

AS SAID THREE TIMES HERE >REFIT