Mikepier wrote:
On Oct 25, 1:35 pm, Mikepier wrote:
On Oct 25, 10:03 am, Manster wrote:

The OP said he was screwing the oak to the joists. Anyway, a 1/4"
Hardibacker over the oak would give it some density, however ripping it
out is overkill and 1/4" plywood is good for cabinet backs, not
sub-flooring. Also the Hardi or Wonderboard does not need to be screwed
to the joists. Ya want proper? Place an actual mortar bed over the
sub-floor for a tile base.


What if I used an anti-crack membrane over the oak floor?

It would help I'm sure.


OK, I think I'm going to tear this floor up and just lay in a 3/4
plywood. I tried taking up some of the floor and it looks like it's
coming up easy, so I'll just do it the right way. Thanks for all you
inputs.


Then glue and screw the plywood to the joists, followed by 1/4"
Hardibacker over that plywood.