Flooring Tile - tile on an uneven floor

I have recently started to undertake finishing my basement. I am picking up where somebody left off. I am currently finishing up some drywall and will soon be turning my attention to the unfinished protion of the flooring. I have a walk out basement that is carpeted (making it a pain to tape and texture drywall). Near the walk out door there is ceramic tile for about the last 3 feet up to the door. But the tile was left about 6 inches from the wall/door. After inspecting the situation I realized why. The footings and the walls where poured in too different pours, and they are not even. The last six inches would cover the space where these two concrete pours meet. My quesion is, how do I go about finishing this area? I thought I could even up the floor by packing a fairly dry mix of cement into the uneven part until it is even, then finishing in the tile. But I am not sure if this is the correct route to go. Any advice or ideas on what I should do to finish this area are greatly apperciated.

Thank you in advance.

Bob

Assuming from what you describe the foundation is in fact lower than the slab. If that's the case that's good, maybe.

You are correct that you could fill the lower area. What you must consider is the "movement" (up and down) that may be occurring on a regular basis from season to season.

You must also "honor" THAT joint in the two concrete components.

I would suggest you buy a suitable (thickness) tile that looks good with the existing tile. Use this new tile to cover the old (filled) area and continue that new tile all-around the existing tile creating a border.

Will this work?:thinker:

Thank you for the reply.

What you have described is exactly right. The foundation is the lower part of area that I need to cover. I have considered that the two concrete pours might shift, which is why I posted this question rather than just lay the tile the best way I know how. So is there a joint compound that will hold the tile securely and still allow it to move a little without breaking, that I should consider using? If so how would I go about grouting in that area? I like the idea of using a thick decerative tile on the edge. I will be looking into that.

Thank you,
Bob

Fill the low areas with a Portland cement patching product. Install the tile with a "real" modified thinset tile mortar. Grout the joints between the tiles with a Portland cement grout and fill the expansion joint crack (grout line) with a color matching caulk. Nothin' will stop the floor from shifting or the tiles from moving up and down if that's what they choose to do so you have to plan for the possible movement.

The use of the somewhat flexible colored caulk will be the only thing that might last for a while. May last forever.:)

Thank you Bud.
It sounds like a good plan. I'll give that a try when I get to that point.

Bob