Hi, Im installing my first ceramic tile floor, and am not sure how to proceed. I have a subfloor right now of 3/4 inch wooden planks and then 1/4 inch plywood.

Can I remove this plywood, and put down 1/4 inch cement board right on top of my 3/4 inch planks, and then tile right on the cement board? The problem is that this new ceramic tile floor will be right next to a hardwood floor for about ~20 ft (I am removing a wall and attaching my kitchen to my living room) The hardwood floor in my living room is about 1/2 inch above the wooden planks, so I only have 1/2 inch to work with if I want a level floor without installing new hardwood. Any suggestions would be appreciated.

Thanks!