I am about to tile my 5x8 bathroom floor. I am using Hardibacker board. Right now, I have a plywood
floor that I am going to thinset and screw the hardibacker to. I laid a 4' level across the floor.
In the middle of the floor (horizontally), if I press the level down on the right side of the 5'
wide floor), the left side is up at least 1/4" and almost 1/2" at one point. While I have no real
problem if the floor is slightly off level on the whole, I do not like this small buldge that seems
to be in the middle of the floor. I tool a smaller 1' level and laid it all over the floor and it
slightly rocks back and forth. If the level does this, the tile will do this too.

Will the thinset under the hardibacker board level this out? What is the best way to level this
floor?

Tony