I have posted a few questions in the past, and have gotten a huge amount of help - Thank you! The house is getting there! Here's my next project: The garage and den of my 1958 ranch house on Long Island are both on the same slab of concrete, although the den may be a little higher. The rest of the house has a full basement underneath. The previous owners had installed approx. 3 layers of vinyl or linoleum flooring in the den directly onto the concrete. The room also has hot-water baseboard heat. My wife and I do not want to install carpeting, and we really hate the flooring that is there now. I have thought about building up the floor to the same level as the dining room and trying to match the white oak flooring there, but I think that is beyond my capabilities. Our current idea is to remove the layers of old flooring, clean the concrete, fill any cracks, holes, etc., and install large ceramic or porcelain tiles or some other stone flooring. The advantages are that I would not have to build up the floor, and therefore deal with moving the pipes for the heat, and I think I can apply the thinset (or mortar if stone) directly to the slab. I understand the floor will be a little cool, but we would probably put in a nice area rug, and my yellow lab really enjoys the cool surface now in the summer!
My questions are: (1) Do I have to be concerned with moisture coming through the slab? If it does get a little moist, is it going to wreak havoc on the thinset/mortar/tiles/stone? As far as I can tell, this has not been an issue in the past. There aren't any stains on the floor now, and none of the vinyl tiles have curled or gotten wavy. (2) Do I need to prepare the concrete in any way before installing the tiles or stones? And finally, (3) How thick are some of the more common stone flooring materials? I know that I can install the tiles without running into issues with the baseboard heaters, but I am not sure about stone.