Water UFH Decoupling required on a Gyvlon screed? - Tile Advice

[richard8688]

Just looking for some clarification.

I have a 28 sq metre screed slab, Gyvlon Thermio liquid screed, with wet UFH. The laitance has been taken off and it's fully dried. There are no cracks.

After its been primed with APD, will BAL rapid set flexible fibre be ok without a decoupling mat?

The BAL docs say 'may' be used. They appear to only say that the mat is mandatory on wooden substrates.

If a mat is requied, how much adhesive should go under it and on top? 6mm notch trowel above and below mat?

Tiles will be travertine.

Using the mat adds another £500 of materials...ish... 2 layers of adhesive and the mat...


Cheers!

 

[Time's Ran Out]

It's travertine -
Personally I'd use Tilemaster primer, Tilemaster Gyvlon screed adhesive , Ditra mat, Tilemaster fast set flexible white adhesive, Tilemaster beige grout 3000.
Make sure the UFH has been run and off before tiling.

 

[Lee@emctiles]

same as above, TM do an anti fracture mat if you want a one stop shop for everything.

And yes, it is advised a decoupler is used when natural stone is being fitter ontop of ufh.

 

[richard8688]

Thanks chaps!

If I'm using a decoupler, what trowel notch sizes would you use below and above the mat? 3mm below, 6mm above? Or still use a 10mm circular on top?

 

[hmtiling]

Thanks chaps!

If I'm using a decoupler, what trowel notch sizes would you use below and above the mat? 3mm below, 6mm above? Or still use a 10mm circular on top?

I would use 4mm below and 10mm above with tiles back skimmed. I use a Karl Dahm underlayment roller for ditra/durabase which i find very handy

 

[Time's Ran Out]

I use Doc Martins size 8 and 13 stone body weight!
Under the Ditra 4mm and above whatever I pick up to fit the tiles as I trowel the floor and the tile.

 

[widler]

I'd use the TM matting along with primer, tilemaster anylfix and use stamdard s1 or rapid o top of matting.
Or equivalent

 

[Dumbo]

Me being picky I use 4mm notch under Ditra or dural and 3 mm under flat mats like bal rapid Matt.

 

[richard8688]

So TileMaster is a better choice than BAL, yes?

 

[Lee@emctiles]

So TileMaster is a better choice than BAL, yes?

i dont think there is much of a difference in the two @richard8688

 

[hmtiling]

I assume tm will guarantee their mat with anhyfix and bal won't guarantee with gypsum addy. If the case tm is the better choice imo

 

[Dumbo]

I assume tm will guarantee their mat with anhyfix and bal won't guarantee with gypsum addy. If the case tm is the better choice imo

Call me sceptic but has any body made a claim against an adhesive manufacturer guarantee and they have just dealt with it.

 

[hmtiling]

Call me sceptic but has any body made a claim against an adhesive manufacturer guarantee and they have just dealt with it.

hahaha. Nope, i've never heard of one just holding their hands up but Tilemaster have a great reputation, engage with fixers and stand by their products. Also, why would't you use gypsum with gypsum when the guarantee is there?

 

[Dumbo]

hahaha. Nope, i've never heard of one just holding their hands up but Tilemaster have a great reputation, engage with fixers and stand by their products. Also, why would't you use gypsum with gypsum when the guarantee is there?

As I said guarantees are worthless . It was. Delete as appropriate . To wet, to dry, to cold, to hot , what primer ! .
I have had adhesive manufacturers tell me OK to do a job a certain way then when I ask them to send a written spec saying the same They then backed out .

 

[hmtiling]

As I said guarantees are worthless . It was. Delete as appropriate . To wet, to dry, to cold, to hot , what primer ! .
I have had adhesive manufacturers tell me OK to do a job a certain way then when I ask them to send a written spec saying the same They then backed out .

Have you had a few failures then?