Putting in either a thermal wire/mesh (SunTouch) type underfloor heater or carbon film under tile.
The subfloor is OSB. Going to pour 3/4" of LevelQuik Self-Leveling Concrete (replacing Gyp-Crete that was removed) and then thinset and tile. Which is the proper layer for the underfloor heating to go in? Energy efficiency is of minimal importance.
Pro of putting it in the concrete is it would survive a re-tile job, possibly? Whereas putting it in the thinset below the tiles means it's junked during a retile. My only worry is that it wouldn't heat properly if it was in the concrete layer.
Best Answer
With the sun touch it goes on a mat under the backer or cement. The thicker your space to the tile is the more even the temp will feel and it won’t be bothered if you decide to retile. I thought it was so nice I put it im 2 of my bathrooms.