Help!: Tiles not set and falling off?

[Riker007]

Have done tiling myself many times and never ever had this problem. For some reason tiles won't set properly on wall, two have fallen off and a lot of moisture is present. When pulling off spacers that are stubborn a tile might come off, that was two days ago but customer rang to tell me two tiles have fallen off allegedly on their own on the top row. I think they are ceramic tiles, can't tell difference between ceramic and porcelain as didn't buy them, can check packet when I go back! About 200mm by 300mm so not huge tiles. Wall was painted surface in cloakroom, used ready mixed adhesive as always and this time they appear not to have set. Used this stuff many times before and stuff always set nicely after even after a few hours. Half of tiling I used the Cerafix (?) adhesive, other half was Wickes own brand heavy duty stuff which from memory set better than the other stuff. Until I go back and have a better look, I'm told its the tiles that were used with the Cerafix stuff that haven't set. Is it feasable to remove these tiles if haven't set and reapply another adhesive so they won't fall off again? Or replace tiles also? Could it be damp from this one wall (though was bone dry) or is it a funny paint I've tiled onto?
No didn't use any primer, never had to before when tiling straight onto a wall. No brown biscuit backing either. Whats the remedy for the wall now if reappling tiles, assuming they won't set if I wait long enough?

[Matt]

I would imagine it is due to the paint. Tubbed adhesive needs the moisture to be sucked out of it before it dries. With tiling onto a painted wall, the moisture won't have anywhere to go apart from the tile

[GirlRacerRed]

hi Riker

did you use a primer on the paint before you tiled? and did you sand back/score/key any of the paint before you tiled?

to the best tilers forum by the way

[whitebeam]

Did the tiles have a brown biscuit back, they would be ceramic. I would have used powdered ahesive for that size tile, if they were porcelain and the walls are painted it has no where for the moisture to dry the addy will dry on the edges but the middle will remain damp for a long time.
If the paint was a vinyl silk it will not take any moisture whatsoever

[Sean fsy]

make sure the wall has not had any wall paper on it previously as we all know that the paste on the wall just goes back moist when adhesive is applied on to it.

[Dave]

How thick did you apply the adhesive..?

[Riker007]

Used standard wall trowel, whatever that size is. Plenty of adhesive all over tile. Covered all over tile evenly, and at the time they stuck nicely to wall and didn't move off at all..

[whitebeam]

How long have you been tiling out of curiosity ??

[Riker007]

Been tiling about three years. Plumber by trade, sometimes do tiling... So anyone any pearls of wisdom?

[whitebeam]

The tubbed gear has to be 3mm max bed, also the paint may have released itself from the wall due to the moisture from the addy.

I would visit the job and check the tiles, if they come off easy you may have retile.

The adhesive will come off the tile easy, use powdered from now on with the bigger tiles.

[faithhealer]

Seen a few loose 'walls' lately, all 'Tubbed addy! Worked with another tiler last week and converted him, he is now a big fan of mapei P9!

[Riker007]

In theory, given the situation, if left will the adhesive just set after time? Surely the grout will help sprevent them falling off, and in time, the adhesive will set and presto! U think?

[Dave]

Is the adhesive stuck to the tiles or the wall...or both..?

[whitebeam]

In theory, given the situation, if left will the adhesive just set after time? Surely the grout will help sprevent them falling off, and in time, the adhesive will set and presto! U think?

No, the addy is dispersion and needs air to dry plus some suction from at least one surface.

No, the grout will not stop moisture penetrating, it's moisture resistant not waterproof and the addy can soften with the water.

[Riker007]

So I should just leave it a while to set? Or just bite the bullet and re tile the half with the possibly not so good adhesive? Is PVA a good idea?

[whitebeam]

Don't pva, that could cause more grief

[Riker007]

Just the tiles were given the adhesive, as every other tile needed fiddling with to get them level with the next one as wall so out. So am I right in thinking that if the tiles aren't too bad, they will set naturally, or should I take them down, sand down the wall, scratch it etc then reapply tiles with powdered adhesive?

[faithhealer]

Just the tiles were given the adhesive, as every other tile needed fiddling with to get them level with the next one as wall so out. So am I right in thinking that if the tiles aren't too bad, they will set naturally, or should I take them down, sand down the wall, scratch it etc then reapply tiles with powdered adhesive?

answered your own question there mate

[beanz]

You need to know why they are coming off before you make any decisions. Have you looked at the tiles? Are they coming off with Addy and paint attached? Or just Addy? If the wall was badly out, i'm guessing a fair amount of packing out has been done? If so, addy will never dry. I've seen people just grout in that situation, but the only thing holding the tiles on is the grout, and eventually the lot will come away from the wall.
Best to just strip em now, while the addy is still wet enough to get of without breaking tiles imo.

[Riker007]

Umm yes when I was there one one came off it had paint on it. Bloody paint. I really don't wanna start again it took long enough....!! I'll see tmrw when I go to job, not looking forward to it one bit. Post later on when I get back, as travelling away to get to job. Typical. I hate this god damm house. May try leaving a heater in the room for a while to see if that helps them set...fingers crossed

[whitebeam]

Where you from Riker

[Riker007]

I'm from Hastings, East Sussex but the job is in Sutton, Surrey...

[whitebeam]

fair distance.

I was in hasting watching the march and fireworks on the 17th

[Riker007]

Good fireworks aren't they? All for free as well, even better. I'm from the Surrey area originally, and job is for a friends mother. Its always the way, if you know the person well, the job goes wrong! Why why why... Gonna have to come up with a valid reason by tmrw as well, should be interesting

[faithhealer]

Paint doesn't sound good does it? If they fell off at a later date and fell on someone who are you going to blame?

[Riker007]

I blame the person who used shoody paint on their walls. Scum. Well I don't know the true picture till tmrw, so time will tell

[whitebeam]

Did the paint have a mist coat, how much history on the walls.

Just say that the paint was'nt applied correctly which lead to a possible falure and you will put right, what more can you say

[Riker007]

I blame the scum bag who painted the wall! Can I assume that if I take the tiles down, wipe off the adhesive, the new adhesive will bond properly to tile even though old adhesive stained back of tile? Whoops i said the painter was scum twice on two posts by accident, nevermind. Yes good idea, blame the painter, if paint applied properly it shouldn't have come off at all...

[whitebeam]

Sorry but going to ask more questions, was it recently plastered, was the paint just finished without a mist coat

[Riker007]

Not recently plastered at all, house built probably in the fifties. Did it have a miscoat, I don't know.. However now you mention it, the lady had painted above the tile line, and had problems with paint peeling off when she painted. So no, probably no miscoat.. Bugger does that mean re tile the lot, or just the half with the Cerafix adhesive?