Help!: My porcelain kitchen tiles are lifting - help.....

[d8wyt]

We put down 40sqm of porcelain tiles in the kitchen. We have under floor heating which we commission for weeks before the floor was laid, we used flexible adhesive. It begun to lift a few months after it was laid. The tiles lift then the grout crack. It has only done this in parts of the kitchen not the whole kitchen. Please help as we had it fixed and it has done it again so would like to fix it permanently!!

Thanks

[jay]

can you lift a tile and then take some pics might help

also what adh was used

[Bri]

Welcome along to the forum. Could you give us a bit more info, such as the brand of adhesive, is the UFH piped or electric, was the grout flexible, did you run the floor temp up gradually after the adhesive and grout had been given time to fully cure.

[Dave]

Hi..

What substrate is it.?

[d8wyt]

I can take a picture, but not sure about lifting the tile. Yes we did gradually heat the floor up. It was a flexi adhesive and grout we used but unsure of the brand as we have used it all!! It was laid on ply floor.

[d8wyt]

Piped!

[Dave]

Substrate..?

[hillhead]

Sounds like the ply is the problem again.
Bounce? movement at joints?
Was it screwed down properly etc?

[d8wyt]

Sorry unsure?

[d8wyt]

Yes husband sayes it was as it was a new floor - new extension etc...

[d8wyt]

Substrate?

[Dave]

Sorry unsure?

What floor type is it..

Timber.. concrete.. screed.. pourable screed.?

[hillhead]

She said laid on ply Dave.

Did you're husband tile it himself?

[jay]

She said laid on ply Dave.

Did you're husband tile it himself?

yes but whats under ply

[Dave]

She said laid on ply Dave.

Did you're husband tile it himself?

just seen the reply after my first one.. oops.



So what thickness ply and again what substrate as in what is the ply laid onto..? we need this info before we can progress.

[d8wyt]

He did a new extension and put down a new floor including joists - not a solid floor - does this help????

[Dave]

So is it chip board..? and what thickness was the ply..?

[d8wyt]

Chipboard flooring, with glued 6mm ply and screwed every 3 inches. He has also left expansion between ply. It is not moving on the joints either?

[Dave]

There is the problem.. 6mm is not suitable.. Now do we call an ambulance now..

[TMTservices]

man alive! 6mm? big no no!

[hillhead]

6mm ply is no good.
BS recommend 15mm minimum.
Not many layers in 6mm so the can lift easily.
Exterior grade ply is needed too.
What make of adhesive??

[jay]

Recommend you lift the lot and go again sorry not the info you would of liked

[d8wyt]

Can't re-ply as the kitchen is on top?

[d8wyt]

I really cannot remember the make of adhesive. However, we did buy it, along with the grout, from a specialist tile shop whi knew what we were doing! Having said that when my husband laid it the adhesive went off very quickly and was difficult to lay. Also we laid the same floor upstairs, using the same grout, adhesive, ply - different tiles - and it is perfect!

[hillhead]

Was the adhesive in bags?

[d8wyt]

Yes! I cannot understand how if we used the wrong ply why the whole floor and grout is not lifting and cracking and it is only in specific places. We have put the same flooring throughout 3 rooms e.g. utilty, kitchen and breakfast room and it is only lifting in part of the utility and kitchen?

[hillhead]

How did your husband apply the adhesive?
Did he put blobs on tiles and place them on floor?
Spread on floor with a notched trowel?
Spread on tile with trowel?

[d8wyt]

spread on the floor with a notched trowel!

[hillhead]

Thats the right way plus the flat edge to put adhesive on the back of the tiles help the bond too.
You have the wrong thickness of ply, this alone can cause tiles to lift. There is movement through this ply.
If adhesive was setting too quick then bad bonds are likely in areas too.
Most could fail over time !!
Bad news i know, temporary you could lift and re stick affected tiles with a two part adhesive S2 grade and keep fingers crossed but good luck (you'll need it).

[Daz]

It seems to me that the wrong materials have been used, i.e. plywood. The plywood that you have used is even more vulnerable to moisture than 18mm (which is still slightly "iffey"). You said that the adhesive seemed to go off quickly, so I would assume that the first few spreads from the mix were wetter than the latter spreads, therefore there will be more moisture exposure in localised areas.
Did hubby prime the underside and sides of the plywood prior to application?
Was the face of the plywood primed prior to adhesive application? If primed, what primer was used please?

Has the problem occurred in areas where there is high foot traffic?

Daz