hardibacker board for leveling wavey surface

[rudypup]

can i use hardibacker boards to level up the surface of a fireplace recess? if so wot adhesive shall i use?:smilewinkgrin::smilewinkgrin:

 

[DHTiling]

You can only use hardi 250 if you are adhering to a flat wall, then you have to mechanical fix as well.... but i have replied to your original thread..