Very strange cracking in new wall tiles...

[kevster310]

Hi there,

Had my bathroom refitted about 6 months ago... Whole room was retiled with 30cmx60cm tiles. It was a complete remodel so all the old tiles and plaster boards were removed.

About a month ago, I noticed that 2 of the tiles over the shower area have developed a very fine but noticeable crack... interesting thing is that the crack runs the length of both tiles from one end all the way to the other so the crack is 120cm long! And if I run my palm over the crack, it feels as if the area is "dented in".

Can anyone advise what would cause tiles to crack like this? I would ideally talk to my builder to get him to remedy the situation but he has apparently shut down his business.

Any tips would be greatly appreciated! I wouldn't want to fix this myself but I just want to know what causes things like this and whether or not it was poor installation...

Thanks!

 

[Richard C]

Whole room was retiled with 30cmx60cm tiles. It was a complete remodel so all the old tiles and plaster boards were removed.

My guess is this a wall can you confirm? What type of board were the plasterboards replaced with & how were they fixed, stud or dot & dab?

Did he tile the floors as well? What did he tile over?

About a month ago, I noticed that 2 of the tiles over the shower area have developed a very fine but noticeable crack... interesting thing is that the crack runs the length of both tiles from one end all the way to the other so the crack is 120cm long! And if I run my palm over the crack, it feels as if the area is "dented in". Can anyone advise what would cause tiles to crack like this?

They are fairly large tiles, is the crack horizontal or vertical? Could be over a board joint & the boards have moved!

I would ideally talk to my builder to get him to remedy the situation but he has apparently shut down his business.

Of dear that’s unfortunate; 6 months is no time at all to be experiencing failure & I fear the worst. Many builders think they can tile but all too often get it wrong. Was he reputable? Did he do an otherwise good job?

Any tips would be greatly appreciated! I wouldn't want to fix this myself but I just want to know what causes things like this and whether or not it was poor installation...

Without seeing it in the flesh, you really need to provide as much information as possible regarding the walls/construction, what materials the builder used & exactly what he did; pictures are usually of help in this situation.

 

[kevster310]

Thanks for the reply Richard,

Yes, the crack is over an exterior brick wall... I seem to recalled that he put varnished plywood over the brick before tiling... I have no idea whether or not this is acceptable behaviour. It's unlikely that the brick wall has cracked as I saw it before it was tiled over and it seemed to be in good condition.

The crack is horizontal (as are the tiles) and it could be possible that the underlying plywood has moved.

For the rest of the bathroom, he tiled onto waterproof cement board screwed onto studs, at least that's what he told me. The quality is so far quite good as I haven't noticed any other problems.

I'm afraid I have not much other info, the rest of the tiles are all fine. He did 2 bathrooms, including the floors and the kitchen floor. Only this one wall has cracked and this is the only brick wall.

Thanks for the help!

 

[Richard C]

I seem to recalled that he put varnished plywood over the brick before tiling... I have no idea whether or not this is acceptable behaviour. The crack is horizontal (as are the tiles) and it could be possible that the underlying plywood has moved.

OMG what on earth possessed him to use varnished ply; you should never use ply of any sort as a wall tile base; its wood & wood isn’t dimensionally stable when damp/wet. My guess is the ply has either got damp & warped or delaminated if it’s not WBP or it’s moved on the fixings; how did he fix to the walls, over stud or direct fix? Can you also advise what type of external walls you have, cavity or solid brick?

For the rest of the bathroom, he tiled onto waterproof cement board screwed onto studs, at least that's what he told me. The quality is so far quite good as I haven't noticed any other problems.

Why on earth didn’t he use waterproof cement backer board in the wet area as well, do you know which one he used? Using backer board in dry areas & ply of any sort in a wet area makes absolutely no sense to me at all.

I fear you may end up having to take the tiles & ply down & redo with cement backer board.

 

[kevster310]

Thanks for the reply... that's what I feared...

He used cement board in all the other areas (including a second shower room) so I assumed that the brick wall was special in some way. I think he directly screwed the ply onto the brick wall.

The cement boards he used were green, that was the only thing I noticed.

I think the brick wall is solid, it's a shared wall in a terraced house.

Is it possible that he put cement board over the ply? If the ply under the cement board got wet, could it still cause similar problems? I definitely recall he used plywood but the next day I checked it had already been tiled over...

I will attempt to contact him again and maybe the tiler as well... any advice for when confronting him?

This whole project has been a big disaster to start with... the surprising thing is that he came very well recommended and he has apparently done very big projects in the past... oh well. You live and you learn.

 

[lancenotalot]

Are you sure the green boards were cement as they are usually grey in colour.
Green would lead me to belive it is moisture resistant plasterboard

 

[Richard C]

I think he directly screwed the ply onto the brick wall.

Well that’s never going to be good news unless he packet out in some way to accommodate for any unevenness. A common method used for fixing cement boards is to dot & dab them in place using adhesive & than mechanically fix through the adhesive dabs into the wall behind once the adhesive has set.

The cement boards he used were green, that was the only thing I noticed.

Are you absolutely sure it was cement board & not just Moisture Resistant plasterboard which is green faced; that would make more sense!

I think the brick wall is solid, it's a shared wall in a terraced house.

So it’s a dividing wall, not really an external wall. Solid brick external walls in older properties can be prone to damp & the possibility of moisture ingress from outside into the back of the ply was what was going through my mind; that would have been even more serious.

Is it possible that he put cement board over the ply? If the ply under the cement board got wet, could it still cause similar problems? I definitely recall he used plywood but the next day I checked it had already been tiled over...

I can’t really imagine why he would do that but who knows; but even so the damage is already done with the wood ply.

I will attempt to contact him again and maybe the tiler as well... any advice for when confronting him? This whole project has been a big disaster to start with... the surprising thing is that he came very well recommended and he has apparently done very big projects in the past... oh well. You live and you learn.

Tell him politely that you want him to put it right but if he’s ceased trading your hardly likely to get much joy. Only other course open to you is the small claims court but even if you win your case, he’s hardly likely to cough up if he’s not trading & if he’s limited liability (Ltd) & liquidates the company you’ve had it!

If you do end up ripping it all down, use the right materials & if your not sure post here for advice.

 

[Richard C]

Are you sure the green boards were cement as they are usually grey in colour.
Green would lead me to belive it is moisture resistant plasterboard

My thinking as well, just a little late in getting it in

 

[kevster310]

Thanks for all the advice...

The boards were green and I was told it was cement board... but he could've told me anything as I would have had no way to check... dishonest builders are hard to catch...

I will try to contact him again.

Thanks for all the help