Cracked tiles on UFH

[afright]

Hi,just need some advice,I did a bathroom 10 months ago and have just got a phone call from the customer saying that 6 tiles have hairline cracks,been to have a look and 3 tiles have cracked on either side of the heating mat.The floor area is 4 m2 but the mat is only 1 m2 in front of the toilet,the customer supplied the tiles (from Wickes) and he prepared the floor with NMP and then the UFH mat before I tiled.Being a small mat I just tiled direct over it using Mapei flex, and tiles are stuck solid.My dilemma is once I remove the tiles I am bound to damage the mat,as I never supplied or fitted the mat would it be down to me to replace the UFH mat at my expense ?.This has never happened to me before and cannot see this is down to fixing error as the floor is solid,any advice would be grateful,thanks.

 

[Andy Allen]

What were the tiles?.....it wasn't that Johnson wall and floor tile thats more wall tile than floor tile.

I know wicks sell them.....a customer had some last week..

 

[afright]

They was 33 x 33 ceramic not theJonhnson type wall and floor.

 

[Chalker]

They was 33 x 33 ceramic not theJonhnson type wall and floor.

Ceramic on a floor , over ufh, there's the problem.

Customer supplied, so IMHO, not your problem. ( maybe should have advised against ceramic)

 

[Andy Allen]

What was the quality of the tile like?
Trouble is the adhesive is so good now a days a cheap tile will fail with any movement before the adhesive gives up..

 

[afright]

Just a normal cheap ceramic ,I have done a lot of floors with ceramic like the tiles that I used over UFH never with an issue ,I have said I will remove without charge but if I damage the mat which I reckon,that will have to be renewed just dont want to be at my expense and it will bound to happen again.

 

[Andy Allen]

Im assuming it was a wooden floor?
If so was there much deflection?

 

[afright]

Yes wooden floor no deflection.

 

[Time's Ran Out]

Lots of issues here, starting and ending with the customer doing the preparation!

 

[Sean SML Tiling]

Agree with you there John. I offer no warranty when customers do prep work themselves. Yo don't know whether the nmp is actually fixed correctly. Have they only just cracked?

 

[Spare Tool]

I too have had a problem with using ufh with nmply, and they wernt ceramic, cracks appeared in granite after about a year. On lifting a few i found the cracks were directly in line with the edges of the nmply boards, the nmply was glued and screwed and glued together on the edges. If you had leveled over the mat before tiling you might have got away with lifting the tiles carefully, cleaning up the adhesive, thin slc, fitting ditra or similar then retiling as i did, but in this instance i wouldn't have thought the tiles will come up without ruining the mat. On my job i got the customer to supply the new materials and tiles and i provided the labour free of charge. It was a local job in a small village and it kept my reputation intact to offer free labour.... No problems since

 

[afright]

Yes it does look its cracked on the edge of the mat as the customer laid the mat and nmp maybe I could use this to my advantage and say that he pays for the mat if damaged .

 

[White Room]

As TJ, I would'nt have let him do the prep...

 

[AliGage]

Not sure what nomoreply or hardie etc suggest in their datasheet. But a tile backer (cement type) are still subject to expansion when heated. I'm sure one of the products like this suggest a 5mm joibt between boards.

 

[Sean Kelly]

You will damage the mat when lifting 3 tiles. By pulling up on the tile you will probably stretch the cable. I tried to save a customers UFH mat a few years ago when she had her bathroom re done. It is virtually impossible unless you dot and dabbed!!!!!! (Joke - sorry!)

What's to say you did manage to replace 3 tiles. You will probably need to change another three by Summer.

You will have to go back to the customer and explain about his prep work and his materials. I guess supplying the labour free will put your mind at rest, but I would not be replacing items I did buy.

Was this job done on a tight/small budget? Did you offer to lay SLC?

If it was a bigger room and there was no option but to smash up 3 tiles, and you did stretch or damage the cable then a repair will cost £360.