A Andrew Owens TF Arms Nov 17, 2022 #2 At minimum you would need an uncoupling membrane Ditra or Dural etc if the ply is rock solid if not 6mm cement boards Hardibacker or No more ply.
At minimum you would need an uncoupling membrane Ditra or Dural etc if the ply is rock solid if not 6mm cement boards Hardibacker or No more ply.