I'm redoing the flooring in my laundry room and hallway of my older home. I removed three layers down to the original subfloor, installed OSB, and then laid an uncoupling membrane using modified mortar. I used unmodified mortar to lay down large tiles (16x32 inches), but they keep coming up. I didn't back butter the tiles – is that where I went wrong?
3 Answers
It's hard to pinpoint the exact issue without being there, but when laying tile, you’ve got to do a coverage test. For floors, you’re shooting for at least 80% coverage and even more for outdoor or wet areas. Make sure you're using the right trowel and spreading the mortar evenly. Also, with large tiles like yours, back buttering is definitely crucial. So yeah, not back buttering could certainly be your main problem.
I've done a few tiling projects, and I swear by Schluter All-Set. It works wonders for me! Always back butter your tiles. It’s one of those jobs where you want to get it right the first time. If I skip that step and the tile doesn’t stick, I know I can only blame myself.
What type of trowel are you using? Square notch or V notch? Also, when you say the tiles didn’t set, do you mean they popped up or the mortar just didn’t cure? If it’s the latter, switching to Schluter All-Set is a solid choice. But back buttering is really important, especially for those larger tiles. And make sure your tiles are clean and dry before setting them!