Can you lay hardibacker on top of 9mm ply

[RKyls]

Hi, we are getting our kitchen re-done and having the floor tiled. The previous owner has put 9mm ply down and used a vinyl over the top, however he’s plyed underneath the cabinets.

A few tilers have mentioned about using hardie backer but some have suggested ripping out the ply underneath. As it’s not good to apply Hardinbacker to ply?

Can someone please advise?

Thanks in advance

 

[Spare Tool]

Long as you screw through the ply and into the subfloor it'll be fine so I'd suggest 35mm x 4 turbo gold screws..

 

[Dougs Third Go]

what's underneath the ply?, surely not 9mm ply onto joists?

 

[Dougs Third Go]

anybody else? I'm intrigued to find out if it's a 9mm ply onto joists,,

 

[GoneGuy]

anybody else? I'm intrigued to find out if it's a 9mm ply onto joists,,

I’m assuming 9mm ply over floorboards that are worn or uneven?

 

[RKyls]

Unsure, we moved into property 4yrs ago. Hallways and living room are floor boards so presuming it’s the same underneath.

 

[Flintstone]

It's easy to use a multi tool to cut the ply where needed Insitu if you want to lift it.