Blown and cracked tiles..Help!

[AJ47]

Hi, my first post.

First just to say hello and that I think this site is really good. I have been looking at it and it seems to be full of really helpful knowledge and advice. I am a customer not a tiler. This is my story so far.........!

We have been renovating an old house and have run into a big problem that maybe one of you maybe able to give some advice as to how we progress from here.

We subcontracted the tiling out to a local company that had done a superb job on a friends kitchen floor, which had underfloor heating too. The work was to lay about 40 sq meters of 80x80 SaloniVisual Crema tiles. The floor would already be prepared as follows;


100 thick concrete over site to BS8500
80 mm thick insulation board, (Celotex was used)
Separating layer of sheet polythene min 125 microns or 500 gauge
Underfloor heating coils for water based system secured in position with proprietary fixing clips. The installation of the coils were laid in strict accordance with the heating engineer's and manufacturer's recommendations and instructions
75 mm thick sand cement screed finish


The floor was left for about a month until the heating was turned on for testing. Then off about 2 days before the tiler arrived. The tiler found that the tiles were really difficult to cut but seemed to do a good job and laid them in about 3 days. He used flexible adhesive. This was about 3 weeks till Christmas. We asked (twice)the tiler and supplier if we could turn the heating on on Christmas day and both said yes, no problem. We started at 16 degs c increasing 1 deg each day until 20 degs max.

After 2 days or so we noticed hairline cracks on about 5 tiles, that had been cut ( the tiler had left an expansion gap) and also upon further investigation about 70% of the tiles appeared to be ’blown’, mostly in the corners of the tiles. Later when we lifted a tile we noticed that the adhesive had stuck to half the tile and half the screed.

We are at a real loss at what to do now. We have arranged a meeting with the tiler and a rep from the adhesive company to try and find a solution, but not being a tiler I don’t want to be bullied into accepting something that isn’t up to the standard that you would except of a £4000 job!

If anyone could give any suggestions I would be really grateful.

Regards AJ47

[Sir Ramic]

Can i just clear a few points up here.
75mm sand and cement screed?....should be left a minimum of 75 days to dry. 1mm per day .
As for turning the heating on at a start of 16 degrees ? it should be on its lowest setting and then increased daily as slow as possible IMO.
You say tiler left an expansion? was that around the perimeter ?
You say 40m2 but what was the longest length? Were any expansions placed anywhere else?

[AJ47]

Thanks Sir Ramic for your reply. Just to reiterate I am the customer and on a very steep learning curve! We did as we were told and in fact the building contractor turned on the heat but there was no evidence of screed failure before the tiles were laid. Yes, there is an expansion gap around the perimeter. The longest length is about 12 m approx.

[Sir Ramic]

Who turned the heating on to 16 degrees after the tiles were laid ? This seems to be one problem, i feel that was to high initially.

Longest run of tiles 12 metres ? there should be an expansion joint along there somewhere.

I think that when the tiler and adhesive rep turns up all that will happen is that the blame will be handed around and i feel that you will get the blame for turning the heating on so high so quick.

However i do wish you a sensible outcome to this matter. Please let us know what happens in the future.

[CJ]

Was the screed clean?

What I mean is......was it dusty, and did the tiler prime it in anyway.

It does sound like the UFH has been turned on to fast and too high.

[Dave]

Read this..

http://www.tilersforums.co.uk/tile-a...rol-joint.html

[AJ47]

Is that an expansion joint in the screed or tile adhesive, as far as i know there are no expansion joints. The room is openplan orangerie type of build. There is a wood burning stove near by which was on at the time so the ambient room temp was probably between 12-14 degs when I turned it on. It was very difficult to feel any heat coming off the floor.
Thanks for your input, I will let you know what happens. But it sounds expensive!

[AJ47]

Thanks CJ, the floor was swept but not primed.