do I have to remove the vinyl floor covering or can I just put the cement board over it
If it is only one layer of tile you can work right over it as long as the floor is leveled.
You can lay right on top of the vinyl. Just make sure there are no uneven areas in the subfloor before you start.
The vinyl acts as a moister barrier, so go ahead and keep the vinyl down. as long as it is level you are fine. You shouldn't have more than a 1/4 inch dip over a 10' space.
i about 95% sure you can install the cement boared right over the vinyl floor covering.go to hgtv and i am sure they will have your answer on there web sight but i am almost sure you can do it.
