I am getting ready to install ceramic tile in my kitchen. While removing my cabinets i discovered particle board. More research led me to discover I have a 1/2" plywood, then tar paper, then 3/4 particle board, then vinyl, then 1/4 luan. All in very good shape. I plan on putting down 1/4 hardibacker. Is the floor suitable or should I still remove the particle board that is sealed on the bottom by tar paper, and on top by vinyl?