I am going to replace the tile on my kitchen floor. Part of the kitchen floor (~25%) covers an area by a sliding glass door, that was added onto the kitchen. This area used to be a porch, and has since sunk a bit since the addition was put in (we estimate it has been there since the '70s). Consequently, the floor on that area is on a slight downward angle, compared to the rest of the level floor.
I want to lay down long tile in a herringbone pattern. I'm afraid that if I lay it down on the existing subfloor, the tiles that straddle the point where the floor changes slope, will eventually crack/break.
Everyone I talk to say I should lay down self leveling concrete and level the entire floor, but I'm looking for alternatives on how to handle this situation. Any ideas?
Best Answer
Assuming that you have a suitable subfloor (at least 1-1/4" thick and not particle board), and that the floor isn't settling further with time, there's no reason to expect that cracking will occur. Your thinset mortar, properly applied, will support the tile and prevent movement.
That said, it may be wise to look at using a self-leveling material to flatten things out beforehand. You don't say how much the slope ends up being, but a 3/8" by 1/4" notched trowel can only accommodate so much change in plane before voids start to occur.