Falling tiles

[Meatymc]

Just fully tiled the bathroom including the bath side and end panel. Done this several times before but on this occassion the tiles keep working loose and dropping off the bath panels - both side and end. Searched through the site and other sources and seems its due to the fact I PVA'd the board to make it waterproof. Sure I've done this previously and never had any sort of problem before but I could be wrong.

So now I have panels that have a PVA coating on the surface but then a layer of adhesive from after clearing up the dropped tiles. Where the tiles meet the walls they are firmly attached and i don't want to start taking them out and re-boarding.

Are there any solutions out there or is it a ball-ache start all over again on untreated board?

As usual, any help appreciated.

[ayjay]

PVA under tiles has been done to death, possibly on this forum, but certainly on others, it's a NONO.

http://www.ultimatehandyman.co.uk/tilin ... se_pva.htm

[DTWCeramics]

It's a fun one!

take the tiles off of the board, scrape off remaining adhesive, sand down the board (or just simply replace it)

Might be an idea to instead of using a board, use a waterproof backer board and tile directly to it next time?

Cheers.

[Meatymc]

Cheers Matt - resigned to starting again.

Ayjay - may well have been done to death but when you're an amateur and are simply repeating a process you've used successfully in the past, you don't think it won't work again. And sealing something absorbent that is going to be in a damp environment sort of makes sense - or at least does to me

[DTWCeramics]

Unfortunately PVA'ing is really a process that isn't up to standards anymore, in the past it was frowned upon but still done, but with modern tile adhesives and all the specs, it's just not acceptable.

If you have any further questions, read this article on the UHM website: http://www.ultimatehandyman.co.uk/tilin ... _panel.htm

Just use a board like Marmox, Hardibacker, Webiboard, Jackoboard etc, these are all concrete composite boards (waterproof to boot!) and are VERY easy to install.

No need to prime, just tile on top of, grout and it works perfectly.

Hope this helps.

Cheers

[Meatymc]

Cheers Matt - much appreciated

[haveagohero]

As already said instead of PVA use SBR (from builders merchant) but personally i can't see the use of PVA on a bath panel being the cause of failed tiles. Cement board is a better substrate to tile to as well. Something that has not been mentioned though is movement, did you leave any sort of gap for movement of the bath? a bath full of water does drop quite a bit and if the panel is bowing under the weight this will cause the tiles to fall off. Also cheap WBP ply can weap resin that causes tiles to fail

[ayjay]

but personally i can't see the use of PVA on a bath panel being the cause of failed tiles.

Read the link in post 2 of this topic.

It's a common problem.

[haveagohero]

I'm a tiler by trade so i know perfectly well that PVA is a no go for priming and always use SBR when i need to prime but there are a lot of tilers out there who still use PVA and failures are not that common, back in the bad old days when i was serving my time we used to PVA everything before tiling and never had a failure so i doubt that just the fact that the panel was PVA'd is to blame for the failure.

Another consideration is the type of tiles that were used and the adhesive used to stick them, if they were porcelain and tubbed gear had been used then they would definately part company with the adhesive very quickly, so are the tiles falling off the adhesive or are the tiles falling off with the adhesive still stuck to the back of them?

There are a lot more things to consider besides the use of PVA

[DTWCeramics]

We use tubbed gear to stick Travertine, solid porc tiles, never have any problems.

Modern adhesives are made to different standards from what they were used to be! used to be chuck it up and leave it there for a few years!!

PVA is the most likely cause of failure here, hero :)

[Meatymc]

Haven't got around to re-doing this yet - mid-way through fittinmg a new kitchen. Happened to speak to a plumber at the weekend who told me he always uses plasterboard as a backing panel and then silicon sealant rather than adhesive - that's one way I suppose!

I've noted the other comments regarding movement etc and will be double checking everything when I get around to re-doing.

Thanks for all your input fellas!

[DTWCeramics]

I'd never use silly cone as adhesive, it can't take great weight.

costs £10 or so to get a half sized tub of decent kit, stick the few tiles onto a board (even plasterboard!)and then grout it

[haveagohero]

I use a lot of different adhesives for different situations so i know what can and should be used where. I'm trying to make the point that it was automatically assumed that it was the use of PVA that was to blame for the failure without asking any other questions at all about how the OP had gone about constructing the panel, what adhesive and tiles were used etc. there are still adhesive manufacturers out there who recomend the use of PVA before tiling, i would not use any of these adhesives but people still do.