Advice Please : What Has Caused Fine Cracks In Bathroom Tiles?

[A274]

I'm a customer not a tiler but seeking advice please:

I had two bathrooms fitted in Jan/Feb and in late March noticed some tiles had cracks in - fine cracks in the glaze in webbed patterns (NOT directional cracks that you might see where movement has occurred in wall behind tiles). See attached image. In some places the cracks are even worse and seems as though the whole tile has cracked not only the glaze.

I called the builder back and he is blaming the tiles. However I don't think this is the case as the problem only occurs on some of the walls and not others (all walls were tiled from the same batch of tiles).
The difference between the surfaces that have cracked and the ones that haven't is the thickness of the adhesive used. Where it has been thinly applied - (<6mm which is the max depth you should use according to the instructions on the adhesive packet - 'Topps Rapid Set flexible') the tiles are fine, but where it has been used at greater depths (in some places as much as 24mm has been applied) there are cracked tiles. About 13 m2 of tiles are affected.

I would greatly appreciate any advice on what the cause is and how to fix the problem.

Additional details:
Tiles are Topps diamond white matrix tiles which I know are 'cheap' but I used them in a previous bathroom and inside the shower with no problems at all (installed by a different builder/tiler).
Tiles have been applied to a variety of surfaces: wedi board, waterproof ply, waterproof plasterboard, existing plastered walls, but the walls were not made level / square at this point in the process, instead the builder relied on thick application of tile adhesive to correct.
The cracks have only occurred where the tiles were applied over wedi board or plywood, not to any of the existing plastered walls or 'boxed in' structures built from waterproof plasterboard.

 

[Kevbos]

Topps Rapid Set can deal with that depth. Not that I'd ever use rapid on walls. Not being funny. But customer seemed to know alot about prep and the depths of adhesive. Walls were not flat or prepared properly. But if tiles are not coming off or joints cracking. Then the tile which was stated as cheap probably Chinese or Turkish. Is the problem. You can't say you knew there were many different substrates and exact depths of adhesive used. Yet tiles still stuck. And blame fixer after. Sounds like a multitude of sins. I would have refused to tile it. But I reckon alot more to that story

 

[Kevbos]

Topps Rapid Set can deal with that depth. Not that I'd ever use rapid on walls. Not being funny. But customer seemed to know alot about prep and the depths of adhesive. Walls were not flat or prepared properly. But if tiles are not coming off or joints cracking. Then the tile which was stated as cheap probably Chinese or Turkish. Is the problem. You can't say you knew there were many different substrates and exact depths of adhesive used. Yet tiles still stuck. And blame fixer after. Sounds like a multitude of sins. I would have refused to tile it. But I reckon alot more to that story

24mm bed of adhesive. Sort wall out first.

I learnt my mistakes early as a tiler. Tiles are now harder and harder to keep straight flat etc. I wont touch such jobs with a barge pole for this reason. You go cheap this is what happens. Client saw the poor prep said nothing. They tried to make good job. The tiles have crazed. Who do you blame

 

[macten]

Topps Rapid Set can deal with that depth.

Really?
Tiles couldn't deal with it though.

 

[Kevbos]

Really?
Tiles couldn't deal with it though.

Looks like it as they not falling of or joints cracking. Quite simple really.

 

[jobdone]

I have seen this before due to bed depth being to deep and stressing the tile but it was over painted walls so had delaminated, dried, shrunk and cracked the tile.

 

[One Day]

Hey! Don't class all Chinese tiles as cheap and nasty either. The worst tiles I've fixed in the past few years have all been 'British' ceramics. Some of the very best have been Chinese.

(and the Turkish aren't all bad either)

 

[A274]

Topps Rapid Set can deal with that depth. Not that I'd ever use rapid on walls. Not being funny. But customer seemed to know alot about prep and the depths of adhesive. Walls were not flat or prepared properly. But if tiles are not coming off or joints cracking. Then the tile which was stated as cheap probably Chinese or Turkish. Is the problem. You can't say you knew there were many different substrates and exact depths of adhesive used. Yet tiles still stuck. And blame fixer after. Sounds like a multitude of sins. I would have refused to tile it. But I reckon alot more to that story

I learnt my mistakes early as a tiler. Tiles are now harder and harder to keep straight flat etc. I wont touch such jobs with a barge pole for this reason. You go cheap this is what happens. Client saw the poor prep said nothing. They tried to make good job. The tiles have crazed. Who do you blame

To set the record straight: I did not see poor prep and say nothing - the details I included in my post, particularly adhesive depths and the specs on the packet, were not things I knew at the time but have come to light through two months of trying to sort this problem out. A lot of walls were tiled and it didn't seem unreasonable that they would be made from different surfaces (wedi behind shower, plasterboard for boxing in plumbing on dryer side of bathroom etc). They did not look uneven to me. (again it was only later he explained he used adhesive to make corrections). I'm not a builder, plumber or tiler so I employed a bathroom fitter to do the job for me. He did the prep and employed the tiler, and he did not express any reservations about the quality of the tiles.

My reason for posting on this forum was not to apportion blame but to work out what went wrong so that I know what needs to be done to fix the work.

 

[macten]

Looks like it as they not falling of or joints cracking. Quite simple really.

Yep simples.
26mm is too thick and it shrank crazing the weak *** glaze.

 

[Andy Allen]

Yep simples.
26mm is too thick and it shrank crazing the weak *** glaze.

Don't sugar coat it will you !!....lol

 

[Flintstone]

Crap tiles, that's the top and bottom of it.

 

[One Day]

Customers rarely appreciate being told they've bought crap tiles. I blame Topps!

 

[Ian3]

Why do customers buy cheap tiles yet expect great job when paying a tiler

 

[hmtiling]

Hey! Don't class all Chinese tiles as cheap and nasty either. The worst tiles I've fixed in the past few years have all been 'British' ceramics. Some of the very best have been Chinese.

(and the Turkish aren't all bad either)

Agreed, worst i've used this year are British Ceramic

 

[Time's Ran Out]

Why do customers buy cheap tiles yet expect great job when paying a tiler

Because if it was easy they'd do it themselves! As a professional if you don't think the quality of the materials are to British Standards then you shouldn't do it. They'll get someone else but that's life's choice.

 

[Ronski]

Why do customers buy cheap tiles yet expect great job when paying a tiler

Because most people want to save money, and like anything whether it's tiles or anything else for that matter they don't realise the implications, and of course what's to say an expensive tile is any good anyway - the supplier or some part of the supply chain could be ripping people off with a sub standard product. Just because it's expensive doesn't mean it's good, and likewise if it's cheap it doesn't mean it's crap either.

To the OP, when I came on here for help when I decided to do my own tiling, I got a rather frosty response from some, and help from others. This is totally understandable, the more DIY'ers that do their own work the less there is for professionals, also why should a professional give away their experience for free, but if that's the way they feel they shouldn't reply. That said when I was willing to pay a professional to do my tiling in the kitchen because the wife wanted them done diagonally I could not find anyone willing to do it - I ended up paying someone who was not a tiler, but he still done a great job. I'm also a professional in my trade, and I don't mind helping people when they ask.

In regards to your problem as soon as I read the first post I guessed that the adhesive had shrunk slightly, this has caused the tile to bend slightly and cracked the glaze. If the tiler knew this may happen then they should have at least warned you, if they didn't know then I guess they where not that experienced. We all learn (and forget) as time goes by.

When I done my en-suite, we had one area of a brick wall that was very uneven, to get around it we purchased some cheap granite tiles, stuck these to the wall, then roughed them up with a grinder and tiled over them, it worked a treat.