Tiles falling off wall, adhesive not setting

[David Robinson]

Disaster!

Focus Seramiksan 33cm x 25cm ceramic tiles Newly (a few weeks ago now) plastered walls, which I've sealed with Ultra Tile Prime IT FP (mixed with water according to the instructions) Ultra Tile ProGrip HG (purple top tub)

I looked at the "good stuff" (BAL and Mapei), but due to cost and lack of local availability, for these tiles only (the others are porcelain, so needed something better), I was advised the ProGrip HG would be good enough to stick 30cm tiles to nice solid walls. Was this a mistake? ...

I started putting the tiles on last Thursday. I finished one wall on Sunday (not doing it full time! + lots of cuts! + I'm not very fast!)

I went in tonight to remove the wooden batten at the bottom of that wall, ready to start another one. When I pulled the wooden batten off, one tile came off. The one next to it also seemed lose and easily came off.

Behind the tile, the adhesive wasn't set at all! It was still quite soft. It was stuck OK to the wall, but came completely off the tile - except where I'd packed the corner of one tile with extra adhesive, where it was even softer (not dried at all) and stuck a bit of the tile. The adhesive on the wall has clearly been squashed down by the tile - maybe squashed by 50-70% i.e. the original 5mm ridges are now

1-3mm. The wall isn't particularly flat (not the best plasterer) so the squashing was uneven, but even so...!

The adhesive seems to only to have set where it's exposed to the air at the edge of tiles. Many of the tiles sound "hollow" when knocked. In fact it's only the ones where I added extra adhesive to pack them (due to uneven wall) that _don't_ sound hollow - but when I took those off to add that extra adhesive, I could see the tile had been well pressed down into the first lot.

What have I done wrong?

I've found this thread elsewhere...

sounds very similar - but mine are supposedly ceramic tiles. They say they're ceramic. They cut nice and easily with a cheap diamond wheel cutter. The man at the adhesive shop recommended this tile adhesive for them - in fact he recommended this tile adhesive for them only - the other tiles I've got are porcelain (supposedly), for which he sold me a mix-it-yourself job.

Is it true that tubs of adhesive don't dry on A4 sized tiles, like it says in that thread?!

Any help / advice greatly appreciated.

I'm supposed to be finishing this job by having a full weekend at it, but it doesn't look very hopeful now.

Cheers, David.

[Phil L]

my kitchen tiles are bigger than these, about 400 X 200, but they're not ceramic. Mine took over a week before they had set, and even then, I managed to pull a piece off underneath a window cill.

Same as yours, new plaster, sealed with pva, best thing to do is get some air movement in there, I left one ring of the gas cooker burning on low (radiator was removed for decoration purposes and it was March) and put an oscilating fan on the floor, might want to open a few windows overnight too

[The Natural Philosopher]

I bet you have a waterproofed wall or summat.

Leave the batten up for a couple of weeks. It takes a LOT of time to dry through the cracks.

I have personally found that Evostik waterproof DOES set faster than simple air dying cements.

[The Natural Philosopher]

stupidest thing to do, ever.

And the cause of the problem.

Best thing is not shove stupid PVA on new plaster when you are going to tile it.

[Phil L]

adhesive dries out immediately if the plaster is left raw, it's like drying mortar in the sun, it dries before the setting process has completed

What do you suggest instead?

[David Robinson]

blockwork, dot-n-dab, 12.5mm standard plasterboard, skimmed, left a couple of weeks, sealed with Ultra Tile Prime IT FP (NOT PVA!), then tiled a few days afterwards (primer dries in an hour)

That might be a solution, but I can't imagine most people leave battens up for a couple of weeks. Typical advice seems to be to grout after a day or two!

FWIW I've just tried to pull off the first tile, applied Thursday (i.e. 6 days ago), and managed to get it off just by pulling firmly at the exposed edge with my fingers. Adhesive behind this one is slightly damp (or dry-ish!) and crumbly, not solid at all.

I have Ultra Tile ProFlex SP +ES for the rest of it (i.e. the porcelain tiles + floor tiles) - I might just try it with these ceramics. As it's stuff you mix up, I don't suppose it needs air to dry.

Cheers, David.

[The Natural Philosopher]

Exactly,. Just what you want. Tiles grab fast and stick like shit.

Remember nearly ALL wall adhesives don't SET, they DRY. They are not cement or plaster based, especially if ready mixed..how could they be?

So let em dry !

Simples!

Not using PVA.

[The Natural Philosopher]

see you got suckered as well. Why seal?

Trade doesn't and I dont. My tiles stay up!

Thats cos most people don't buy unnecessary sealers either.

If its a mixed floor adhesive, its a bloody strong cement based one.

It sounds like whoever sold you this lot unloaded all the stuff he couldn't sell cos it doesn't work, on you.

:-(

I tried several wall tile adhesives, most went damp and crimbly, and then dry and crumbly, and had all et problems you have, teh first one I tried that really worked was the Evostik. It looks sort of a like sticks like shit, and it was twice the price, but it just 'did what it said ion the tin' so I never went further than that. Life's to short.

Floors all done with ardurit rapid and ardurit flexible.**ING exopensive, but wonderful.

Grout is all Bal.

[Tim Watts]

The Natural Philosopher wibbled on Wednesday 04 August 2010 21:52

I agree WRT PVA - if water gets in there it may soften - but if the application isn't a shower it will be OK. If it is a shower, I suggest the OP gets some really good water resistant grout.

PVA has it's uses, but it is rather overused, especially in applications where it is not suited. Mostly by thicko "builders" (no offense to the OP - but "professionals" ought to know better).

However, BAL *tell* you to use SBR on polished new plaster prior to Greenstar which, whilst that will not fail, it will reduce the water dispersion from the adhesive and probably give rise to a similar issue.

I found no issues with Greenstar - though with 10cm tiles it's hard to go wrong.

I did notice today though, that some Mapei flexible adhesive I am using for tiling onto ply is a rather different beast. Bugger all grab and takes ages to set, especially as it rained outside today (was under a tarp, but the air was humid). Glad I was doing those on a bench rather than with the ply in its final vertical fitting - I could see the latter being a tad of a bitch.

Nothing to do now but let the air sort it out - but it should in time - may take days or a week, but it will get there. Make sure it's had plenty of time before grouting.

Cheers

Tim

BTW:

BAL Bluestar (very much like Greenstar) is 14 quid per massive tub from Screwfix. Even with delivery it's a fraction of the cost of the rest of the job.

Topps Tiles sell Greenstar.

[Tim Watts]

Phil L wibbled on Wednesday 04 August 2010 21:56

SBR.

[Tim Watts]

David Robinson wibbled on Wednesday 04 August 2010 22:08

Right - I missed that bit. Sorry. That sounds like an SBR functional equivalent (for this job). BAL mention sealing with something funky they make, or SBR as an alternative. It would be reasonably safe to assume this stuff is waterproof.

OK - stop worrying. Refix the tiles you knocked off and give it several days at least before grouting, longer if possible.

It *will* be OK.

Cheers

Tim

[The Natural Philosopher]

If its a setting cement, no problems You dont want the wall to dry the cement prematurely.

But if its a DRYING cement, its disaster...

Agreed. It WILL dry as well as its ever likely to. If a cement grout is used that is mildly porous, that's enough to hold tiles in place.

water mixed or pre-mixed?

[Tim Watts]

The Natural Philosopher wibbled on Wednesday 04 August 2010 23:12

Premixed as was the Greenstar I used, which means it must have been a drying adhesive.

I used some proper powder stuff for the floor, but couldn't be bothered with the faff for the wall.

[The Medway Handyman]

I always PVA and my tiles stay up perfectly using Wickes bog standard ready mix tile goo. Ready to grout next day.

[A.Lee]

It happens. If they are not disturbed, then they'll stay in place, if you pull/push them, then you break the bond and they'll move/fall off. Thick tile cement can take a week to dry completely.

Bigger tiles are more prone to it, as there is such a big area to dry out. Mostly, the moisture escapes around the edge of the tile.

Alan.

[A.Lee]

I pay £6 for Greenstar from Topps. I use it for all walls/tiles, and have never had a problem with it. It pays to have a Trade Account! Alan.

[stuart noble]

Tile adhesive sticks to virtually anything from the glazed surface of other tiles to old lath and plaster finishes. Failures are usually due to too much adhesive and/or not combing it with the spreader, which allows air to pass between the ridges. Moving a tile with your finger tips should become virtually impossible within five minutes, by which time it is being held by suction. But if you did manage to move it, you would have broken the bond and, although it may not fall off there and then, it would never stick properly.

[Jim K]

eh? shurely the "slight twisting motion" as you press on firmly is going to flatten those ridges down into a full bed?? that's the point of the ridged applicator/trowel i.e. to achieve a consistent ideal depth of adhesive on the "ideal" flat wall..

Jim K

[stuart noble]

But the twisting motion is only slight. If you take old tiles off you can usually still see the grooves in the adhesive.

[Dave Liquorice]

Even those that sound hollow when tapped?

It is a bit odd that the adhesive hasn't set, is that sealer rather to effective in not letting the moisture in the adhesive into the wall?

It may also be technique when offering the tile to the wall and setting it into position. Place it in the right place the finally push into position with a slight twisting motion, final small (much less than 1mm) tweaks onto the spacers (if using) without the twist. A tile should be firm onto the adhesive and be very reluctant to move after a very few minutes.