Underfloor heating - looking for help

Can anyone personally recommend a contractor who has installed wet underfloor heating into an existing suspended timber floor?

We want to extend our existing kitchen UFH into two adjoining rooms—approximately 23 m²—in Haringey. The work will include lifting/reinstating the floor, insulation, connecting to the existing system and commissioning.

Recommendations from people who have had a similar retrofit completed would be especially helpful. Please say what work they did for you and roughly when.