Do I Need Cement Board Under Floor Tile

I d like to get as close as possible to matching the height of the existing tile.
Do i need cement board under floor tile. This is a distinct advantage over plywood and drywall. Cement board is a type of underlayment that is now standard for most tile installations but particularly for floor tile. Cement board is an easily installed diy tile underlayment providing a stable dependable tile setting substrate while eliminating the complicated lath and mortar floating process. On top of the 2 6 will be 3 4 subfloor thinset cement board redgard thinset tile.
Do it yourselfers can use either 1 2 or 1 4 inch cement board in certain applications while other scenarios mandate 1 2 inch board. The primary benefit of cement board is that it doesn t break down or expand or warp if it gets wet.