Which tile adhesive to use with Schluter Ditra

[Franer]

Hi guys, I'm a homeowner and a DIY enthusiast. I have two small areas to tile. A front hall and a pantry area. Ceramic tiles (small) and using Ditra matt. Both areas are over concrete. From my research online they say it is important to use unmodified mortar. I live in Dublin Ireland. Any advice on which type and brand of adhesive I should use. I know unmodified is an American term and part of the problem was that my info was coming from US sources. Thanks in advance for any help offered.

 

[Dave]

Hi , what reason are you using Ditra for firstly and as for adhesive, yes your info is American based , schluter uk say modified adhesive is fine.

 

[Franer]

Hi , what reason are you using Ditra for firstly and as for adhesive, yes your info is American based , schluter uk say modified adhesive is fine.

Hi and thanks for the reply. I'm using Ditra because there are a few small cracks in the concrete and I'm hoping the de-coupling matt will prevent and movement in my tile down the line. I am also trying to build up to the height of a laminate floor so the few millimetres I'll gain in height will be useful. So any flexible polymer enhanced adhesive will do? On Shluters website they do mention that it may have drying problems. They recommend modified when laying Ditra onto a wood substrate but when laying the Ditra on concrete they say to use an unmodified and for laying the tile onto the Ditra they also say use unmodified. Thanks again for the reply I appreciate your advise enormously.

 

[MitchellGloverLondon]

Use a 3/4mm notched trowel, mix a good quality rapid runny, make sure to rub it in, and make sure you prime if substrate requires.

 

[Franer]

Use a 3/4mm notched trowel, mix a good quality rapid runny, make sure to rub it in, and make sure you prime if substrate requires.

Hi and thanks for the reply. I'm aware of how to install the Ditra and what trowel to use, what I am unsure of is which tile adhesive to use. Have you used flexible adhesive or polymer modified to install tiles on top of Ditra? As the previous posts explain Shluter don't recommend using a modified mortar. Thanks again for your input.

 

[Dave]

Hi and thanks for the reply. I'm using Ditra because there are a few small cracks in the concrete and I'm hoping the de-coupling matt will prevent and movement in my tile down the line. I am also trying to build up to the height of a laminate floor so the few millimetres I'll gain in height will be useful. So any flexible polymer enhanced adhesive will do? On Shluters website they do mention that it may have drying problems. They recommend modified when laying Ditra onto a wood substrate but when laying the Ditra on concrete they say to use an unmodified and for laying the tile onto the Ditra they also say use unmodified. Thanks again for the reply I appreciate your advise enormously.

Go to schluter uk not .com.

 

[Franer]

Go to schluter uk not .com.

Hi again, I copied this from Shluter UK - "Immediately after the Schlüter®-DITRA 25 matting is installed, the tiles can be set using the thin-bed method and using a bonding tile adhesive that matches the requirements of the covering."
So they are saying it doesn't matter but the US Shluter site has a whole article about modified/unmodified, I find that odd in that they are talking about the same product. Have you used modified mortar on Ditra without any problems in the past? Thanks again for your help

 

[MitchellGloverLondon]

Hi and thanks for the reply. I'm aware of how to install the Ditra and what trowel to use, what I am unsure of is which tile adhesive to use. Have you used flexible adhesive or polymer modified to install tiles on top of Ditra? As the previous posts explain Shluter don't recommend using a modified mortar. Thanks again for your input.

Flexible adhesive, Ardex x7r should be fine.

 

[Lou]

@Schlüter-Systems Ltd can you help out?

 

[Old Mod]

You’ll find that most installers in the uk will use the same adhesive under as well as over Ditra25
An S1 adhesive will work perfectly ok,
an S2 however, will not.
And yes, there differences between Europe and the U.S.A. when it comes to methods of installation etc.
Then, they have a Ditra25 cement based adhesive available to them, we don’t.
And yet it’s a European product.
So If you follow the guidelines laid down by
Schluter.co.uk you will be covered,
but not by Schluter.com.
You can also ring Schluter Uk direct and talk to their tech line.

And just as a footnote, if memory serves, in the USA although they use the term
‘unmodified thin-set’ the adhesive still works with porcelain, and by that definition, it must be slightly modified, or it wouldn’t work.
I believe their ‘modified thinset’ is more akin to our S2, and then that statement is correct, it should not be used with Ditra25.

If anyone wishes to correct me, please do.
I’d be as interested as the OP.