There is an area under the threshold to my house that I would like to tile with a decorative tile. There are two things I am uncertain about.

1) The bottom part of the wall is inset from the rest of it. I imagine I need to fill it to provide a level subsurface for the tile, but I am not sure what would be the best way to do this.

2) I assume that the area between the tile and the floor should not be grouted but rather caulked, to allow for freedom of movement. Is this correct? Should the area between the left and right walls and the tile also be caulked rather than grouted?

Photograph of the riser in question

1 Answer 1


(1) I suggest filling the void with concrete. You could probably go heavy on the sand in the mix as it's not structural (for my shower floor I used one part sand topping mix to three parts sand).

(2) I agree on using caulk at changes of plane instead of grout.

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