Tanking required over SLC for Travertine (not wet room) ?

[Indiansandstone]

Hi to all at TF - seems like a friendly place!

New ensuite has enclosed shower so the 2sqm of trav should not be subject to water continuously except for wet feet etc... The SLC is over elec UFH, over 10mm marmox (glued and screwed) boards to 18mm WBP ply at 200mm centres onto noggin'd and shuttered joists (passes the water glass jump test and I'm 16st!)

I read a thread recommending tanking or even Ditra specifically to protect the SLC from moisture ingress (its Mapai Ultraplan Renovation). Is this really recommended or required?

Also I'm planning to bed with a white one part powder rapid set flexi - would ideally minimise the depth of adhesive to 5-6mm, is this realistic with a solid bed trowel? (they all seem to be 10mm depth?)

Thanks!

 

[Time's Ran Out]

I'd always use Ditra with travertine over Ufh and white flexible adhesive with a 10 trowel by the time you press into adhesive will give you 6/8mm solid bed.

 

[DHTiling]

If you have the choice to un-couple , then yes go for it IMO.

 

[Indiansandstone]

Thanks for the reply - am trying to minimise the height due to how close its getting to the low profile try.... (good planning!! )

So what depth of addy woud you say is needed under the ditra, and can i get away with a tilting my trowel to get a thinner solid bed above it?

PS I'm assuming i need to cycle the UFH up gradually once before tiling over as well...

 

[DHTiling]

Ditra is 3mm and the adhesive depth is negligible..

And yes you need to commission the ufh after a period of time to allow the adhesive etc to cure and gain strength.

 

[Alan.P]

I use an old 6mm trowel for ditra, isn't 6mm any more but it's not too bad, as for your trowel method for the trav, stick to proper techniques and you'll be ok, no point spoiling all that prep by poor fixing.

 

[Indiansandstone]

Cheers Dave and Alan - sounds like i need to order some ditra then.... I assume the bags of rapid set flexi are OK for installing it and the trav above?

 

[Sean SML Tiling]

Ditra is 3mm and the adhesive depth is negligible..

And yes you need to commission the ufh after a period of time to allow the adhesive etc to cure and gain strength.

How long would you leave it cure for dave?

 

[DHTiling]

How long would you leave it cure for dave?

On average most suppliers recommend 14 days min..