this is interesting!!

[Diamond Pool Finishers]

[ame=http://www.youtube.com/watch?v=Xw6KA2X0E6s&feature=related]YouTube - Ditra subfloor problem[/ame] never take any substrate for granted!!

 

[DHTiling]

He is a member on the JB forum... i posted that a while back... i questioned why he had not picked up on that before installation dave.

 

[doug boardley]

I've seen this one before, but certainly as gooner says.

 

[Stewart]

How the hell do you miss that..... I love Ditra and use a hell of a lot of it, and i have only had one problem in 1000's of metres of use.

About 6 years ago convinced a customer that this was the best prep to use on a timber floor that had 9mm ply installed on top of 18mm chipboard (refused to tile on top of 9mm ply) Customer said yes and i installed 350 square metres of Ditra and tile. 2 months later, get a call from customer complaining about cracked grout-lines and tiles.
starting to panic, went out to customer and lifted a couple of tiles..... turns out, the plastic top had separated from the flock backing, and i could lift the tiles up like a carpet. Thankfully Schluter accepted responsibility and replaced the whole floor. Rep said a bad batch of Ditra. That said.... by far the best product of it's kind on the market.