Bathroom floor tile

[DKAudio]

I am going to tile my bathroom floor. I know that backerboard/Durarock should always be used but the area is really small (~8X4). Is it still needed or can I use a good thinset like FlexBond right on the plywood? I have never used backerboard before therefore, I have a couple questions...

My house was built in 1954 and there is 1X6 or 1X8 (guessing) boards that run at ~45° on top of the joists. There is then plywood on top of that. Would the backerboard go on top and screw to the plywood? I am asking because once the tile is on there will be a fairly good height difference than the floor it meets to in the doorway.

Thanks

[The Builder]

Henry makes a wetbed type underlayment that you could mix and pour down. Read the manufacturers added additional recommendations. Certain brands recommend a mesh and so forth.

[ceramictilepro]

Schluter Ditra Mat is thinner than 1/4" backer board and imo performs way better and easier to install. Make sure your floor is sound without excessive movement like 1/8" in a 10' span. tip...put a cup of water in the middle of floor and jump up and down to see how much movement there is...it is expected to have some movement just not excessive. I have used ditra mat for years and will never go back to backer board.

I am a licensed contractor that decided to make several video on how to install tile and one of them is a bathroom floor using ditra... i have some nice videos on how to install tile using ditra mat on my website

ceramictilepro