I am going to be putting a ceramic tile floor down in the family room & I need to know do I need to put down cement board 1st or is luann good enough? I've heard it's better to use the cement board, but then I've heard why spend the extra money when luann works just fine.We are going to use 12x12 pieces and the room size is 12'7" x 20'. We want to do it right the 1st time.Any help would be appreciated.Thanks. Tony