Problem with Ditra Installation

cdnNick

One section of the Ditra did not stick to the thinset at all, my 4 year old son pulled it up rather easily and the fleece on the bottom was white and clean. This sheet was laid at the end of the day so I am guessing the the thinset was too dry by then and even though I pushed it down with all my 200+ lbs of weight, using a float, it didn't stick.

My problem is how do I know if the other pieces are are properly stuck down? We walked around and pulled at other pieces but and weren't able to lift any of the edges but how can we trust the Ditra at this point? If the middle isn't stuck down how can I check that?

My wife has been away on travel so I've had the joy of just staring at this issue and not knowing if we are doomed to have our tile install fail or not. I think after this is all done I'm going to stick to working with wood...

JetSwet

What type thinset do you use?
What type trowel did you use?
What did you lay the ditra over?

If you gently pinch and pull the waffels in the middle does it have play?

cdnNick

Versabond modified thinset.
Small V notch trowel, I forget the exact size.
Plywood screwed down to OSB.

It doesn't seem to move if you try to pull up on it in the middle but does it matter is say the middle isn't stuck down for the other edge is? I don't know if that's what happened but I'm curious if that's what happened.

JetSwet

Were you unrolling the membrane in sections wile applying the verabond or did you apply verabond then unroll and lay it? Set time maybe? How was the versabond wile trowling it hard to move around or easy?

cdnNick

We cut all the sections before starting, we put down the versabond then laid the ditra on top and pushed it down with a float. We followed the instructions on the bag of Versabond but I am thinking that it should have been wetter for the Ditra to really soak it in. It wasn't too bad pushing it around with the trowel.

JetSwet

A creamy peanut butter or even mayo type consistentcey you will want.

Chizzle off the dry and reset it in new thinset bach.

cdnNick

It wasn't that consistency for sure, so it was probably too dry for Ditra. Problem is we laid about 160sq ft of it so I'm not sure which parts are fine and which need to be removed.

JetSwet

I think you will have to check it all.
Verabond sets quick imo working small and or quick helps.