QUESTIONWe are building a new home. Builder installed tile but I noticed they put Schluter Ditra under tiles on our shower wall and on our shower ceiling tile (steam shower) when they were more than half down. I pointed it out to the installer and they were quick to cover with rest with tile the next day. Ditra is an uncoupling material made only for floors. I am worried the tile will fail, falling on our heads and causing injury. It is heavy 6lb+ 13x39 ceiling tiles and heavy 4’x4’ wall tiles. Ditra isn’t meant to be used as waterproofing but that is why they said they used it when I asked. I have photos of the tile going in clearly showing the Ditra. Our relationship with this builder is already not good. How should I handle this? The tile itself was close to $10k plus construction and installation costs for this room around $20k. $5k glass surround, $7k fixtures. Spoke with Schluter they said it will likely fail, maybe within the year. I only have a 2 year builders warranty. How should I address this? Do I have to wait for failure/injury if I know there is a dangerous structural installation issue?
ANSWERANSWER - Based on the Schluter literature, although they only show floor applications, they don't say it is only for floors.
The Ditra is waterproof if installed correctly for waterproofing. It does have a key back type of pattern that allows for a mechanical attachment. So as long as the ditra is bonded properly to the wall and ceiling substrate and the tile is properly bonded to the Ditra uncoupling the tile should not fall from the walls or ceiling.
On the other hand, since this is a steam shower, I don't see where Schluter recommends it for steam showers or whether it meets the standards the perm rating for steam showers.
I would get a letter from Schluter stating that the product is not recommended for that use. I would get an attorney to write a letter to the builder with the copy of the Schluter letter asking for them to correct the error. You can take them to Small Claims with this information and/or file a complaint with the state licensing board to mediate it.