H
Hayden Goy
For what good the ply will do for insulation with the ufh then i would just rip it up and tile onto the floor it's self...
Honestly we are not giving you advice to cause you grief, we are here to make sure you have a long lasting installation....Your tiler needs educating as well i think...
Do yourself a big favour and remove the ply...and just tile the floor ...you will probs need to mechanicaly remove the glue but you want the job done right...
The choice is yours really and we wish you good luck....
that would mean me ripping the kitchen out and i cannot do that.
thanks for your time.