How do we remove the mess left behind by incorrectly installed ceramic tile in our kitchen?
We want to install self sticking tiles but the floor is uneven from the grout left behind. I have breathing problems and sanding is out of the question. We are retired with a fixed income so solution would have to be inexpensive something we can do ourselves. Please help as we have removed the tile 4 months ago and I can't stand the mess much longer.
Chip it away with a hammer and masonry chisel.
Then glue (I know you said you had breathing issues, but...) and screw another layer of subflooring over it.
Not only will that layer of subflooring provide a suitable substrate for your tiles to stick to and help level things out, but it should also help eliminate the deflection issue which caused your tiles to crack in the first place.