is there such a thing as mechanical fastenings for large/heavy stone tiles

[Stuart L]

I recently posted a question concerning some 600 x 600 x 10 limestone tiles I have fixed to my chimney breast. These are coming away for the 3rd time. They were fixed using a Vitcas heat resistant adhesive and grout. The answers I got from the forum were not very helpful, so I contacted Vitcus with the same questions. The answer I got back is below,

"We believe the tiles are coming away because of they are a considerable size and weight for our tile adhesive to hold alone and we advise that they are mechanically fixed in place.


When you reattach your tile(s) we recommend that you use our VITCAS Heat Resistant Tile Adhesive with a full 3mm coverage across the whole back of each tile. This is best achieved using a 6mm tile comb which distributes the adhesive evenly and consistently. Our Heat Resistant Tile Adhesive should also be using in conjunction with out VITCAS PVA Sealer. The PVA would need to coat the wall and the back of the tile first, applying the product neat. Once the PVA is sticky and tacky you can apply the Heat Resistant Tile Adhesive to the back of the tile and apply to the wall . You do not need to wait for the PVA to dry fully".

based on this advice from Vitcas I have 2 questions

1) is there such a thing as mechanical fixing to assist holding the tile up? ( please don't suggest drilling the face of the tiles and attaching with screws).
2) based on my reading of this forum there is a resistance from a lot of the members to using PVA, why?

 

[Julian 'Farmer' Bonsall]

' Some of the adhesives are intended for thin (approx 3mm) adhesive beds and will adhere metal to metal, ceramic to metal as well as ceramic to masonry. Others can be used much more thickly where the surface of the substrate is uneven and there is an element of gap filling' - Is this important? What are the tiles stuck to? How hot does it get?

Advice on fireproof tile adhesive - https://www.tilersforums.com/threads/advice-on-fireproof-tile-adhesive.26025/

 

[WetSaw]

I'd use a bagged adhesive rather than ready mixed. There are mechanical fixings for tiles but it's not something you'd normally use in this situation.

 

[Stuart L]

Julian
my original post detailing the problem is
Fire proof adhesive failing on chimney breast - https://www.tilersforums.com/threads/fire-proof-adhesive-failing-on-chimney-breast.85819/#post-902472

the tiles are on flat/new fire board with the recommended 3mm bed.

 

[GoneGuy]

 

[LM]

I recently posted a question concerning some 600 x 600 x 10 limestone tiles I have fixed to my chimney breast. These are coming away for the 3rd time. They were fixed using a Vitcas heat resistant adhesive and grout. The answers I got from the forum were not very helpful, so I contacted Vitcus with the same questions. The answer I got back is below,

"We believe the tiles are coming away because of they are a considerable size and weight for our tile adhesive to hold alone and we advise that they are mechanically fixed in place.


When you reattach your tile(s) we recommend that you use our VITCAS Heat Resistant Tile Adhesive with a full 3mm coverage across the whole back of each tile. This is best achieved using a 6mm tile comb which distributes the adhesive evenly and consistently. Our Heat Resistant Tile Adhesive should also be using in conjunction with out VITCAS PVA Sealer. The PVA would need to coat the wall and the back of the tile first, applying the product neat. Once the PVA is sticky and tacky you can apply the Heat Resistant Tile Adhesive to the back of the tile and apply to the wall . You do not need to wait for the PVA to dry fully".

based on this advice from Vitcas I have 2 questions

1) is there such a thing as mechanical fixing to assist holding the tile up? ( please don't suggest drilling the face of the tiles and attaching with screws).
2) based on my reading of this forum there is a resistance from a lot of the members to using PVA, why? View attachment 98148

Stuart below is a mechanical fixing system.
If you search the forum there is a detailed thread explaining why PVA can’t be used in the tiling world.
RAI-FIX - Raimondi s.p.a. professional tile tools - http://www.raimondispa.com/en/prodotti/rai-fix-gb/

 

[LM]

It’s worth having a read through this also.
New here. Some advice - https://www.tilersforums.com/threads/new-here-some-advice.85061/#post-889848

 

[Julian 'Farmer' Bonsall]

Smart - looks very clever. Some smashing solutions about and i've not idea they exist without people like yourselves.

 

[Stuart L]

Thanks guys , I understand the PVA chemistry thingy now.
Since Vitcas are recommending that you use their PVA, would this indictate that either the Vitcus adhesive does not contain cement or their PVA is not really PVA but something else?

 

[Stuart L]

yeah I think that looks the bees knees, thanks Adey

 

[Julian 'Farmer' Bonsall]

' construction of stoves, pizza ovens, tiled stoves and joining outdoor constructions, such as grills and fireplaces. It has a longer setting time which is easy to use and gives time to match elements.' Is this really suitable to cope with >50kg/m2?

Lee Mac suggested 'ISOMAT AK-FIRE - Adhesives for Special Applications, Tile Adhesives & Grouts - ISOMAT - https://www.isomat.eu/product/isomat-ak-fire-2-en/' - maybe speak to them. Also this thread

'High Temperature Tile Adhesive - https://www.tilersforums.com/threads/high-temperature-tile-adhesive.76657/'.

 

[Stuart L]

Julian
the isomat link says its a refractory mortar for fire bricks, would this be suitable for tiles?
Being a DIY'er i'm not sure if this is suitable for tiles. I will give em a call tomorrow and let you know what they say.
Just looking at purchasing one of those Raimondi tools best price i've found so far is £85 without grinder.

 

[Julian 'Farmer' Bonsall]

Stuart - Im just suggesting you give them a call as they have a large range of solutions and have been helpful to me (recently, and technically). I don't know how hot your wall is getting and how that will determine the solution but clearly you have a bonding issue. The adhesive you have used I see sold in maybe Toolstation and I couldnt find out very much data which I would normally find for adhesive products (I read because I am a DIY'er also and rely on these fair gents and ladies).
What is the fireboard (I think you said you didn't know).
How hot does it get and thus what does a supplier have for >50kg/m2 stone tiles and there instal guide. The use of PVA if one was bedding them like a brick slither on a fireplace or fireoven sounds very different to your application.

 

[Stuart L]

Hi guys
just a follow up on yesterdays conversation, i've been in touch with isomat and the news is not very good. Bellow is their response

"Dear Sir good morning.

I hope you are fine today.

Initially, I would like to thank you for considering ISOMAT products for your project.


Unfortunately, I have to inform you that we do not have an appropriate product in our range for that kind of application. AK-FIRE is not suitable for tiling.

Have a nice day!

Best regards
Cordialement

For ISOMAT S.A.

Georgios Syriopoulos
Civil Engineer MSc
Technical Support Department"

 

[Blunt Tool]

I’ve done them over the years and never had any problems. I’ve used a bagged S1 adhesive like Weber low dust spf and added in some Weber ad250 additive and grouted with a flexible powder grout. Primed walls first with acrylic primer diluted then neat and never used mechanical fixings unless over 3 metres. Notch the wall aswell as small notch the back of tiles.