Tiling on a Floating Floor

[Mr Grinch]

Morning all,

My kitchen has a floating floor and wondered what the best way of tiling it. I had it done 5 years ago but was shafted by a so called Tiler and it wasnt done properly. Some tiles have cracked and some of the tiles sound hollow when tapping them and the grout has come out in places. Im now in the process of getting a few qoutes from local trades but of course the more knowledge i have the better position i will be in when speaking to the tiler's.

How would you do it ?

Any help and info would be gratefully received.

G

[Colour Republic]

Don't tile on to a floating floor would be my advice.

But do you really mean a floating floor or do you mean a suspended floor? Some people confuse the two

[Mr Grinch]

Hi,
Its defo floating. No joists, the insulation was laid on the concrete then chip boarded on top.

At the moment its tiled but the idiot so called tiler, tiled straight onto the chip board. I got him back after the whole thing crunched under foot. He agreed to re do it using flexi adhesive BUT he only did this in the main walkway of the kitchen (found that out later). Around the edges he had left and tiles have cracked and starting to come loose. So far, ive waited 5 years, to try and get some wear out of it but enoughs enough. I want to get it done again but properly this time.

So, ive got a few tiler's in to give me qoutes. This time tiler's that have been recomended, above board and registered company's. So far ive had three different way's of doing it and i dont know who to believe. This seems to be a common thing with Trades. I had this problem with my electrics. Many different ways of doing the same thing. Some say "oh dont do it that way thats wrong" but from someone who is not in the business its very difficult who to believe.

One tiler has said that he would use 8mm ply then detra mat it then use flexi adhesive and grout, another trade said he would use 6mm ply then use a "floating floor matting" (not detra though) with flexi adhesive and grout. The third tiler said he would tile traight onto 10mm ply using the flexi stuff. I have a 4th coming around on Monday. So far i have many solutions but which is correct ?? There is a price difference of £500 from the cheapest to the most expensive !!

In the ideal world, i would screed it BUT the kitchen is already in and would make a complete mess not to mention the cost of it, so im going for the tiles. As i already have said, the tiles in the centre and the walkways are fine, completly solid, no cracking at all BUT the tiles where the flexi stuff hasnt been used and probably over a join in the chipboard the tiles have blown.

HELP im baffled and confused

ps: Would a porcelin tile be stronger than a ceramic ? But again ive heard different opinions about them like "yes porcelin is much stringer" then "i wouldnt get porcelin as it stains easy" to "ceramics mark and chip easier but are easier to lay" - WHO DO I BELIEVE

aaarrrrrrrrrrrrhhhhhhhhh

[Colour Republic]

Ok first things first

Ply at 6/8/10mm is unsuitable as the moisture from the adhesive when setting can delaminate the ply. If you were to overboard then a tile backer board would be much more suitable.

But stop! You need to sort out any movement of the floor first. Ditra matting allows lateral movement of the floor (i.e. side to side) it DOES NOT sort out deflection (i.e. Up and Down) which is why most floating floors are unsuitable to tile over.

Flexible adhesive will help but I wouldn't guarantee it won't crack, the reason it seems to of held up in the hall is because the surface area is much smaller and narrower, whereas on an open floor deflection becomes a big problem. In addition I would use an S2 flexible adhesive rather than an S1 to help even more. But in all honesty the floor needs to be sound before any tiling takes place.

Porcelain tiles are stronger but to confuse matters there are different grades, not all porcelain stains in fact most don't, some require a sealer others don't.

I realise the above doesn't really help but you situation is very specific so the spec of the floor can vary greatly in order to give you the best outcome

[Mr Grinch]

Thanks for your reply.

So basically all the tiler's so far are suggesting something that isnt right. How the hell do i get around this ? These people are supposed to be proffesional but all the qoutes and how to remedy the problem are obviously

With regards to my previous post, the firm solid tiles laid at the moment are in my kitchen and not the hall. The tiles in the centre of the kitchen are fine, just round the edges and in the main door way where the garden doors are.

From memory of what the floor was like pre tiling, there was a bit of deflection in a couple of places, mainly joins in the chip board. Would not the ply board cover this ?

I wish i'd got a solid floor now. Trouble is, i wasnt given the option

[Colour Republic]

Ply would cover it but modern ply is not of great quality and can delaminate even more so with the thicknesses you have been quoted for. you could use marine ply but then that is creating a barrier for the adhesive to truly take the best bond it could, so tile backer boards are a much better option and cheaper. But the fact remains, the deflection needs to sorted, flexible tile adhesive do have some give but they aren't bendable neither are tiles.

Did you see the Tiler lay the tiles? Can you remember if he combed adhesive on to the floor or did he place blobs of adhesive then set the tile?

[Mr Grinch]

To be honest, i cant remember. I think he combed them on. Well that was the first time. He then came back when the whole thing crunched and supposedly re did it using the flexable adhesive, but unfortunatly i could not get the time off of work to watch him.

Two of the new tilers had a jump about on the floor and said that there was neglidgable movement but this was obviously with the current tiles on it.

If i suggested say a 10 or 12mm ply instead of an 8mm with a suitable seriously flexable adhesive (did you say Stone Fix S2 is the best?) and maybe a flexable grout like FG112 from Stone Fix aswell as the Detra matting would that be a better option ? If not the ply then maybe a Backer Board ? What thickness do these come in ? Would it give the same rigidity as a ply board ?

Once again thanks for your reply

[Mr Grinch]

Ply would cover it but modern ply is not of great quality and can delaminate even more so with the thicknesses you have been quoted for. you could use marine ply but then that is creating a barrier for the adhesive to truly take the best bond it could, so tile backer boards are a much better option and cheaper. But the fact remains, the deflection needs to sorted, flexible tile adhesive do have some give but they aren't bendable neither are tiles.

Did you see the Tiler lay the tiles? Can you remember if he combed adhesive on to the floor or did he place blobs of adhesive then set the tile?

One of the Tiler's also mentioned Durabase matting. Is this the same as Dita ?

Confused

[Rookery]

I wouldnt ever tile onto a floating floor because the movement will cause the tiles & grout to crack. Equally I wouldnt tile direct onto chipboard either. In this case I would remove the chipboard and insulation, screw battens to the concrete at 300 c/s, re fit the insulation and chipboard, and overboard with 6mm Hardie backerboard. Then tile using a flexible adhesive and grout.

[Colour Republic]

One of the Tiler's also mentioned Durabase matting. Is this the same as Dita ?

Confused

Yes Dural CI+ is a decoupling membrane as is Ditra. They are similar products from two different manufacturers. Just ensure if Dural is used you get the newly designed matting not the old one where Dural had problems with batchs made late last year.

[davemulheran]

Your predicament sounds EXACTLY like my conservatory!

Foam insulation with chipboard, laid on to a concrete substrate.

I had cracked grout/ tiles and loose tiles. This is what I did:

I ripped up ALL the flooring.
Primed the concreste sub with Primer G
Used Mapei flex tile adhesive and laid 40mm marmox boards
(then fitted UFH, levelled with latex and tiled on to that)

SOLID floor now (I hope)

Hope that helps
Dave