My husband and I are putting down new tile in the kitchen. We busted up the old tile to discover that they put the tile down on 3/4 in plywood over the subfloor (so, it's subfloor, then plywood, then tile). What to do? Do we clean up the plywood and tile over it again? Do we tear up the ply and use backerboard (we bought 1/4 in backer thinking we would need it). How exactly do you tear up the ply if they used screws and glue to put it down on the subfloor? Do we just put the backerboard over the ply and "deal with" how much it will raise the kitchen floor over the surrounding hard wood and carpet?? Help please, we put tile in the mud room fine, but we used backer board. I REALLY don't want to screw this up, please help!