Ceramic over existing tile

My kitchen and hallway are tiled (possible asbestos). This tile is very well applied and will be a major job to remove. This tile was purchased over ten years ago from The Bay and is the same tile they used in thier stores. I would like to lay a sub-floor over it and tile over that. What would be my best choice for this? I have been told not to use OSB for this.

In the industry "tile" means ceramic tile not vinyl composition tile (VCT) you're referring to. You're asking whether to install an underlayment (not a subfloor), and then ceramic tiles.

Chances are there is a thin (1/4") underlayment under the VCT, this needs to be removed for best results. After that we need to evaluate how the subfloor system is built to make sure it's stiff enough for tiles. (probably is). You then install a cement backer or membrane then the tiles.

BTW, if your floor was made after the early-mid '80's there is likely no asbestos.

Jaz