Hi all
Im after a bit of advice please !
we are in the process of laying matt porcelain tiles over a ceramic tiled floor in the kitchen. The exisiting floor is sound and level (we just dont like it!) and have used ready mixed adhesive/grout and a week later we still seem to have tiles that are not stuck down....
Around the edges of the tiles seem to be set solid but in the middle of tiles the adhesive hasnt yet set (we dug one up and the adhesive was still soft in the centre with only about a centimetre border around the outside having set). We havent grouted yet as were told it would take longer to dry so have allowed a week rather than the stated 48 hours but am just wondering if anyone has any experience of this and any idea just how much longer it will take to dry?
any responses would be appreciated as its quite a large area (35 sq metres) and the thought of taking it all up is depressing!
thanks in advance

I'm afraid you have used the wrong adhesive, there is nothing for it but to pull the floor up, clean, then start again

What is the name of this adhesive. Tubbed adhesive is no good for floors and definately not for porcelain tiles or tiles of this size...Totally wrong.

yes,take it up.did someone sell you this knowing it was wrong i wonder????

Ready mixed adhesive with porcelain tiles is not advisable as the tile will not absorb any of the moisture from the adhesive as stated before it can take a hell of a long time to set on the floor. What size trowel was used? How big are the grout lines spaced for? Also with it being a lot colder now that will also effect the drying time of the adhesive.

Originally Posted by Sir Ramic

What is the name of this adhesive. Tubbed adhesive is no good for floors and definately not for porcelain tiles or tiles of this size...Totally wrong.

Its Unibond Extra Strong Waterproof Adhesive and Grout ........ we asked in about 3 different tile places and two of them said it would be okay but it would have gone off by now wouldn't it

Is it maybe because they are bigger floor tiles ? they are 50x50 rather than the 30x30 we have underneath......
So will it never go off at all ?.....

Originally Posted by Mammamia

Its Unibond Extra Strong Waterproof Adhesive and Grout ........ we asked in about 3 different tile places and two of them said it would be okay but it would have gone off by now wouldn't it

Is it maybe because they are bigger floor tiles ? they are 50x50 rather than the 30x30 we have underneath......
So will it never go off at all ?.....

Utter rubbish. Take them up and re tile using a cement based adhesive for porcelain tiles.

Originally Posted by craig4749

Ready mixed adhesive with porcelain tiles is not advisable as the tile will not absorb any of the moisture from the adhesive as stated before it can take a hell of a long time to set on the floor. What size trowel was used? How big are the grout lines spaced for? Also with it being a lot colder now that will also effect the drying time of the adhesive.

Trowel is 4mm notches and the grout lines are about 6mm (used tile spacers)

they are 50x50 rather than the 30x30 we have underneath...

So you have tiled on tile as well..?

Originally Posted by Mammamia

Trowel is 4mm notches and the grout lines are about 6mm (used tile spacers)

4mm is only suitable for mosaic !

I agree with Sir Ramic, need to lift them then use a powder based floor adhesive which is cement based. A flexible one if going down onto a wooden floor and if concrete non flexible. Im not a tiler I only sell tioles but I know the tilers at my neck of the woods would use a larger notch trowel than 4mm most would go for an 8mm, this will also allow air to get under the tiles to help the adhesive set quicker.

Originally Posted by Dave

So you have tiled on tile as well..?

Yes, we have. We were also told that this would be OK as the existing floor is sound (concrete underneath the ceramic tiles). Is this not the case?

If nothing changes, will the adhesive never set? I now realise that it's not the best stuff, but ripping the whole thing up will be a big job for us.

Originally Posted by Sir Ramic

4mm is only suitable for mosaic !

Apologies, the trowel is 8mm.

It may set yes, but could take weeks However from what you have described it doesnt seem the tiles are actually sticking though, I understand it may be a big job but I feel you have no alternative but to lift them, as the longer you leave them now the harder it will be to get the adhesive off the tiles in order to re do the job.

Cant find teh spec on this adhesive (funny that eh ?) does it say suitable for Porcelain?

OK, thanks for the advice. I guess we'll have to learn the lesson and lift them.

Since they're stuck around the edges (and we'd like to re-use them if possible), should we hire an electrc tile remover (such as this one HSS Hire › Floor Tile Remover) or will this break them?

Also, is BAL rapidset adhesive with porcelbond plus in powder form the best option for adhesive (assuming we're still going to go over the top of the original tiles, which I would imagine will be a lot harder (and messier) to get up?)

Thanks very much for the advice so far.

Originally Posted by Mammamia

Yes, we have. We were also told that this would be OK as the existing floor is sound (concrete underneath the ceramic tiles). Is this not the case?

If nothing changes, will the adhesive never set? I now realise that it's not the best stuff, but ripping the whole thing up will be a big job for us.

I would have thought it would takes months (maybe never) for the adhesive to set, think of it like this, you got the adhesive out of a tub and you have effectively created another tub of the floor by sandwiching the adhesive between 2 non-porous materials

Did the shops advise you to throughly clean the existing tiles and rough them up prior to overtiling? can't believe they sold you tubbed gear for this

Originally Posted by Mammamia

Yes, we have. We were also told that this would be OK as the existing floor is sound (concrete underneath the ceramic tiles). Is this not the case?

If nothing changes, will the adhesive never set? I now realise that it's not the best stuff, but ripping the whole thing up will be a big job for us.

You have 2 surfaces and neither are absorbant..I am truly sorry to say but you have been advised wrong..That adhesive will never set as neither air can get in or moisture can get out via the joints or substrate...The tile is too large for the moisture to escape via the joint in a short time scale..it could take months to fully escape and even then if you have used more than 3mm or so in depth the tensile strength might not be enough to hold them down through lateral expansion of the different substrates.....

So IMO you have been very wrongly advised on the adhesive choice for those tiles...

If you look at this way....when the lid is on the tub of adhesive ..air cannot get in and cause it to set..so by using such a large tile you have in theory put the lid on, if you see what i mean...Dispersion adhesives like that are not designed for you have used it for..

Originally Posted by Sir Ramic

Cant find teh spec on this adhesive (funny that eh ?) does it say suitable for Porcelain?

It's this one http://www.diy.com/diy/jsp/bq/nav.js...LAID=266888106

The chap in the shop said it would be OK to use (we were very clear that we were putting porcelain on top of ceramic tiles) and he said it would just take a bit longer to dry. The sad part is we have spent more than £200 on the adhesive alone....

Just remove them now and you will be able to scrape the adhesive off the back of the tile. A quick wash off and you can start again. Clean teh adhesive off the floor too

Originally Posted by Colour Republic

I would have thought it would takes months (maybe never) for the adhesive to set, think of it like this, you got the adhesive out of a tub and you have effectively created another tub of the floor by sandwiching the adhesive between 2 non-porous materials

Originally Posted by Dave

You have 2 surfaces and neither are absorbant..If you look at this way....when the lid is on the tub of adhesive ..air cannot get in and cause it to set..so by using such a large tile you have in theory put the lid on, if you see what i mean...Dispersion adhesives like that are not designed for you have used it for..

You're going to have to get up earlier than that Dave

Originally Posted by Mammamia

It's this one UniBond Tiling On Concrete Floors Adhesive & Grout Extra Strong Beige 4.6L, 5010383131401

The chap in the shop said it would be OK to use (we were very clear that we were putting porcelain on top of ceramic tiles) and he said it would just take a bit longer to dry. The sad part is we have spent more than £200 on the adhesive alone....

Did you but the adhesive from B&Q? The staff (in general) are not really qualified to advise you in such a way.

I would have thought that if you complain about the advice given, you would get some form of compensation

Working in a tile shop makes me embarassed to here this sort of thing I'm afraid you have been taken for a fool. I would defo go back to the shop and make a complaint and look for some sort of reimbursment!!!

Originally Posted by Mammamia

OK, thanks for the advice. I guess we'll have to learn the lesson and lift them.

Since they're stuck around the edges (and we'd like to re-use them if possible), should we hire an electrc tile remover (such as this one HSS Hire › Floor Tile Remover) or will this break them?

Also, is BAL rapidset adhesive with porcelbond plus in powder form the best option for adhesive (assuming we're still going to go over the top of the original tiles, which I would imagine will be a lot harder (and messier) to get up?)

Thanks very much for the advice so far.

You should find they'll come up quite easy.

And I'd use a Mapei product which you'll find much cheaper than BAL. And Mapei are the world's largest manufacture of building materials in the world. You can get it from any www.TileGiant.co.uk store.

Even the description on there website shows it wont do the job
"UniBond tiling on concrete floors is a high strength tile adhesive and grout specially formulated to tile directly onto concrete and screed floors. Waterproof and ready to use, it is suitable for fixing and grouting ceramic and quarry tiles"

You are tiling onto tiles and using porcelain tiles, got those people make me mad!!!

Originally Posted by Colour Republic

You're going to have to get up earlier than that Dave

Originally Posted by Colour Republic

Did you but the adhesive from B&Q? The staff (in general) are not really qualified to advise you in such a way.

I would have thought that if you complain about the advice given, you would get some form of compensation

Yes we did, and lesson learned. We did have a tiler lined up for this but he let us down five times since June - we got a little annoyed and just thought "we'll do it ourselves".

Will go back tomorrow and see what they will do, if anything.

I really appreciate the kind responses so far, as you can imagine we're pretty down at the moment and this really helps - 2 last questions please?

Should we hire the tile remover with a view to being able to re-use the tiles (the tiles are stuck down around the edges quite firmly and there are over 100 down), and is the BAL adhesive the best option? (Edit, I was typing this as Dave posted his comment about Mapei - thank you).

Many thanks,

MM

You wont need a tile remover just a bit of effort with a stiff blade and Mapei would be my choice of adhesive.
Please give B&Q hell for their absurd advice.

I woould also contact Unibond and ask them if this adhesive is suitable for you job. If they say no, which i believe they will, i would then challenge B&Q with this information.

Hindsight is a wonderful thing