Hey all,

When laying tile, is the height of the mortar half of the trowel depth?

I'm trying to lay tile at a specific height and am trying to determine the best way to do that.

One example is that I ripped out some tile and it looks like there's about 1/8" of mortar on the back. Would I use a 1/4" trowel to match that?

Thanks!

At 90* angle a 1/4" trowel will (theoretically) put 1/8" of mortar down. Of course, sometimes it will be less due to angle.

For reference, trowel depth is determined by the tile size, typically. the smaller the tile, the smaller the trowel notch.
mosaic up to 4x4 can use a 1/8" trowel. 12x12 tiles should at a min. be a 1/4x1/4 trowel and many use 3/8. anything over 16 should use 1/2" notch and anything over 24 should use 3/4".

Pick the trowel depth based on tile size, not trying to meet up with an adjacent flooring. If the correct trowel for the tile isn't working with your adjacency, then you either need more or less mud bed or a thicker substrate to make up the difference.