U
Unused Account 1
The subfloor needs to be super secure ,if you tile and someone else did the work ,it comes back to you ,id say the subfloor not secured ,and i like to use ditra,done a few jobs with the ditra heating matt
are you liable....yes
should ufh been put on ply...no
should you tile on ufh without uncoupling....no
should you let a builder prep the floor ready for you to tile....only a fool would unless you over see every step and every details done to your spec.