Newly fitted tiles falling off!!!

[RichD1]

I've just finished tiling a small upstairs loo. Yesterday I heard a bang and one of my first tiles I fitted had fallen off. When looking at it as it was in a difficult location under the soil pipe it was not fully bedded. I then buttered the wall with a little skim of adhesive and then put a full layer of adhesive on the tile troweled off with a 6mm notched trowel. Went back on fine.

I've been tiling over a period of 4 days and the one that fell off had been on for 3 days.

Yesterday I completed all the tiling and today I've removed the spacers and found several which were loose and fell off. Some tiles had the adhesive stuck to them, in other areas the adhesive was stuck to the wall. All adhesive was powdery still and was easily removed.

This is what I did.

Two of the walls had been re-plastered using hardwall and then skim over to finish. I then PVA'd them. The remaining wall was the original render which I tiled over 30 years ago. The room temperature has been around 10C to 12C and the tub states not below 5C. I've had tiles falling off on all walls.

I've used Webers ready mix adhesive bought from Jewson and the tub has an Oct 2022 date on it. I initially started with applying to the adhesive to the wall but found this difficult, especially as I was not able to fit all the tiles in one go. Senior years I'm afraid! So I reverted to my preferred way of buttering the tile and trowelling off with a 6mm notch trowel. I know this is not the recommended application but it has severed me well for over 50 years and never had any problems. BTW, tiles have fallen off the area where the adhesive was applied as well as where I've applied to the tile. Tiles were buttered individually and set on straight away so no chance for the adhesive to dry out.

Is it because of temperature the adhesive is not drying, but why is some sticking to the tile and in other areas it sticking to the wall.

I've attached images of the tiles and wall. You can see the tiles have 100% coverage with adhesive.

 

[flameport]

I then PVA'd them.

Webers ready mix adhesive

PVA is never required on any surface which is to be tiled.

Ready mixed slop sets by drying out, which is bad at the best of times. Adding PVA to the wall has ensured the only place for moisture to evaporate is thorough the gaps between the tiles.

12C is rather cold even if the tub claims otherwise, and is Oct 2022 the manufacturing date or the expiry date?

 

[opps]

As above, bin the premix stuff and used cement based powdered adhesive.

I would also recommend buying some spacer pegs...

 

[opps]

PVA is never required on any surface which is to be tiled.

And shouldn't ever be used. SBR or similar, yes, PVA no. It can emulsify when wet.

is Oct 2022 the manufacturing date or the expiry date?

Having had a quick look at their site, I think it is the manufacture date.

 

[Swwils]

Your notches also aren't collapsed so those tiles have very little coverage.

 

[RichD1]

Ok, now I’ve got PVA’d the walls what do I do now? Just leave longer to dry?

You say the tiles haven’t been set enough, but it I wiggled them on and tapped with the end of a wooden hammer and they wouldn’t have compressed anymore.

 

[opps]

Ok, now I’ve got PVA’d the walls what do I do now? Just leave longer to dry?

You say the tiles haven’t been set enough, but it I wiggled them on and tapped with the end of a wooden hammer and they wouldn’t have compressed anymore.

You might be able to get away with a coat of SBR over the PVA.

SBR is twice the cost of PVA , but is still a cheap product. You can purchase small bottles from sites like ebay.

I still recommend that you bin the premix adhesive but if you don't want to, at least use spacers in between each tile.

 

[RichD1]

What is the difference between SBR and PVA? Do you think I need to remove all the other tiles and re-do? Should I put some heat in there to dry and aid drying?

Can anyone say why the adhesive has stuck to the tile and not the wall and vice-versa?

 

[tell80]

RichD1,
No heat, dont introduce heat of any kind. The temp is fine.
As above, you'd be better in the long run with taking all the tiles off - scraping the tiles - & scraping the wall.
If the adhesive on the tiles doesn't scrape clean then soak the tiles for however long, & the adhesive will come away.
Again, as above, use powdered adhesive.
Comb the walls and tight butter the tiles unless you have any large tiles.

Keep a damp sponge handy and a bucket of clean water - sponge off any snots or smudges as you work - dont leave them.
The edges of each tile must remain clean, free from adhesive. This allows the grout to take.
IMO, neither Pva nor SBR is typically needed but it depends on suction & ambient temp.
You mention two walls - what about any other wall surfaces?
Skimming is not to be recommended - tile straight onto the solid plaster.

 

[RichD1]

Two walls were re plastered with hardwall and a skim of one coat then PVA’d the third wall was old render which I tiled over 30 years ago.

Are they coming off because the adhesive has not dried out? So should I leave longer before grouting.

 

[tell80]

Thats great that your backing is solid on the three walls.

But I can only repeat what I've already said above. Start again.

Forget about why this or that - fwiw: grout is not meant as an adhesive

 

[oldbutnotdead]

The ready-mix stuff tends to be quite stiff. Powdered is a lot easier to use. Don't worry about the 30 minutes working time on the bag, more like an hour plus in our climate. It's a cement product so there's a chemical reaction when it's going off, doesn't rely on 'drying' so do make sure you clean any goo off the faces and edges as you go.
Given where you are, best bet is pull them all off, clean up, start again with powdered adhesive.

 

[RichD1]

Unfortunately I'm under time pressure as we have some friends coming to stay in a couple of days so need the WC working.

I've gone round all the tiles tapping and prying with my finger nail and have found no further loose. The areas where the tiles have come off does fell damp so maybe the drying time is being extended by the lower temperature and the fact that the wall has been PVA'd. Having said that the old rendered wall was not PVA'd

Interesting that you all say that ready mix is rubbish, but I've used a Weber product and I've always used ready mix on all the wall tiles I've fitted over the past 50 years and never had one fall off.

I think what I'm going to do is leave the tiles as they are and temporarily fit the WC till after our friends have gone home. Hopefully the adhesive will have dried out by then.

Thanks for all your input.

 

[Koolpc]

Never had an issue with the ready mixed tile adhesive myself.

I usually score the walls before tiling too.

 

[oldbutnotdead]

I've used both. Only problem I've had with premix is the stiffness of it- wriggling the tiles to get them flush in all planes was a pain.