It is in my kitchen , hall and bath. Is the reason that tiling is so expensive becasue of having to remove the old tile first?
That's part of it. Rent a chipping hammer. They look like a big hammer drill and come with a 4 wide chisel. that will make short work of taking the old tile off. Work on getting the morter bed chipped downs smooth too. that will make the new tile floor easier to lay.
Its not easy by any means, but its something that I feel most home owners could handle over a weekend. I would recommend that you use a large heavy blade floor scrapper and a big hammer. Basically you smack each tile in the center, which breaks the tile loose underneath then you use the scrapper to take everything off to bare wood.
If the tile was laid properly, it can be time consuming. Yes, part of the cost of laying tile is in removing the old tile floor first. Never tile over tile. That's asking for trouble, plus it raises the floor height. I'd recommend getting a heavy steel mallet or hammer and renting an electric tile jack hammer. It plugs in and has a flat blade attachment that hammers away under the tile to lift it. While it may cost you money, it will save you time and muscle fatigue. Use the hammer to crack the tile before you use the electric tile hammer. It will go a lot faster.
If the existing tile is sound and not loose you can tile over it. You must use modified thin set motar adhesive. The only way to remove tile is to beat it off. Since (as you say) is is directly on wood you may get lucky and the bond is not tight. If this is the case you may get it off using a shovel to scrape and pry. If not safety glasses long sleeves, a hammer and chisel are the way to go.
