Stone tiles not sticking to plywood floor

[BexH]

We have put plyboard down over wooden floor boards and have stone travertine tiles. We have bought Uni bond powder adhesive which we mixed with unibond flexi additive, as per the instructions and applied to the tile. We have laid the tiles and about half have not stuck to the floor, help?! The adhesive is sticking to the tile but not thr floor. Where are we going wrong, can we reuse the tiles that have adhesive stuck to them?

Thanks

 

[DHTiling]

when you say you applied adhesive to the tiles, did you not apply adhesive to the ply as well..?

Oh! Hello and welcome.:welcome:

 

[White Room]

You could try to scrape the adhesive off but travertine are soft and may possibly break in trying.

 

[The Legend; Phil Hobson RIP]

What thickness ply?:welcome:

 

[SandyFloor]

You'll need to give us some further info:

As above thickness of ply?
Size of trowel used?
Did you prime the ply?
Was it immediately clear the tiles weren't sticking?

There are several poosibilities why this has happened so any info you can provide would help.

 

[BexH]

Hi, the ply was 6 mm thick, we didn't prime the ply as the adhesive and unibond additive said not to prime. They stick initially but when we checked the next morning some were loose. Thanks for your help

 

[Tenchman]

Sounds like the ply has absorbed moisture from the adhesive and the tiles are even more porous. sound's like you were given bad advice plus ply isn't thick enough to stop warping .

 

[kilty55]

sorry but 6mm ply is wayyyy to thin ,did u screw the ply down or nail it?

was the adhesive applied direct to the backs of the tiles and what size trowel did you use please? also what kind of consistency did you mix your adhesive too when mixing ,you may have well mixed it too dry or may not have stuck the tiles down properly

 

[White Room]

6mm ply is nowhere thick enough

 

[The Legend; Phil Hobson RIP]

6mm ply as above, not thick enough, will do nothing to reduce deflection. Not a big fan of Unibond adhesive to be honest😳

 

[davy_G]

Hi Bex,
As alot of the chaps said, the 6mm ply is not thick enough to keep the floor rigid although i dont think thats the issue your seeing at the minute as it should not debond the tiles straight away. Unless when you junp on the floor you can feel it moving??
As some suggest it may be more to do with the ply not being primed to prepare it for tiling and the adhesive type and fixing method.
What size are the tiles? Did you back butter them as well as comb the mix onto the floor? Did they get a good twist when in place and did you lift any to check the coverage?
Did the adhesive dry properly on the back of the tiles that debonded?
Was it repid set and if so did you happen to add any more water at any time after initial mixing?

 

[DJS]

I'm also thinking did you lay floor and tile straight away, and was it dusty?

My guess is it was not primed, wrong trowel/not enough adhesive and possible dust contamination being the main factors in why the adhesive should fail so quickly! And how long before you walked on it?

The 6mm ply isn't suitable, so maybe read what the others said above and re-think it before fixing again. Good luck next time.

 

[kevinmarks]

i agree 6mm ply is not thick enough you should really be using 18mm.is the 6mm wavy if so could be not enough glue making contact.what size trowel are you using should really be 10mm.sounds to me not enough glue making contact with ply as ply is to thin and not creating even surface😳

 

[pete f]

Bex stop there and get a pro in to sort it prepping and laying is really a pros job imho it will save you cash in the long run

 

[DJS]

Just read the first post again...travertine!! Definately worth thinking about getting someone in (not just anyone who can tile!).

I'll be laying my first (since I started out as a tiler) 3.5sq m trav floor tommorrow. Was already prep'd with 18mm ply by the customer and he wasn't going to change it!! So I made sure it was screwed down at 100mm centre's, installed DITRAMATT with 1pt flexible rapid set and used a 4mm trowel (which I just got home from doing) and tomorrow I'll be laying the floor with a white 2pt flexible adhesive, and 10mm trowel.

Even with the little experience I have, I'll still be going in with my rear end twitching!! :lol:

 

[DHTiling]

Just read the first post again...travertine!! Definately worth thinking about getting someone in (not just anyone who can tile!).

I'll be laying my first (since I started out as a tiler) 3.5sq m trav floor tommorrow. Was already prep'd with 18mm ply by the customer and he wasn't going to change it!! So I made sure it was screwed down at 100mm centre's, installed DITRAMATT with 1pt flexible rapid set and used a 4mm trowel (which I just got home from doing) and tomorrow I'll be laying the floor with a white 2pt flexible adhesive, and 10mm trowel.

Even with the little experience I have, I'll still be going in with my rear end twitching!! :lol:

Nowt like OTT tile fixing... that will not shift in a million years.

 

[DJS]

I thought the DITRA and latex additive were questionable too, but I wanted to be as sure as I could be (and gain some experience too).

My mate (who is a builder) commented...it's a bit in at the deep end for your first job innit? lol

 

[marshalltiling]

was the ply exterior grade, we had this on a floor prepped by builder with 18 mm ply. tiles lifted after a week with SPF (bal or mapei i think), The ply absorbed the moisture and the adhesive did not stick even with a solid bed. All ply is not the same, it must be WBP and screwed down. Give me a cement based board any day of the week.

 

[borgie]

sounds like dusty trav to me or dusty floor!

 

[DJS]

My job was definately 18mm WBP, and screwed down at 100mm centres. Don't know what grade of 6mm ply BexH used though?

I forgot to mention in my last post that I wiped the floor down twice, left overnight to dry, primed it in the morning and left that to dry for an hour before fixing anything to it.

Does sound like the wood wasn't prep'd right and/or dusty.

 

[aph257]

Hi Denis,
Got your first Trav eh? i did my 1st Slate last week and my back end certainly twitched all day:lol:. I use No More Ply to overboard now its easier to handle than 8' x 4' 18mm ply.

 

[DJS]

Yeah my first big trav job. So much fun, customer really happy with it so far.

I've got a 4sq m en-suite re-fit with slate floor & UFH confirmed for 23rd Aug too...That one will be even more fun!!

Can you send me some details about the no more ply? Ie. Who stocks it/prices etc.

I went to clean the floor up today, and do some final cuts for the walls. The neighbours called round to complain about the smoke alarm that someone had thrown in the skip and had been beeping for the last week and keeping them awake at night (it wasn't me BTW). So I said I would have a dig around and look for it, then they asked me to re-fit their bathroom and tile it too! It's exactly the same as the one I'm in now!! Don't know if I should laugh or cry - dejavu!!

Then they also asked about fitting 20sqM Kardean floor in the kitchen and I wanted to pick your brains about it, as I know you have experience.

Will catch up with you and Mr Baker so will be intouch via email soon.