Just waiting for quotes back from builders for extension & refurb project on my house. I want to install wet underfloor heating (overlay) downstairs and leave the radiators upstairs. I want Honeywell Evohome to control it all.

Is this something builders can do? I assume whoever I use will have a heating engineer. I was going to put some specific instructions in the tender information, but I wasn't entirely certain what they would have to put in exactly. I'm perfectly happy to do the binding and setting up bit, but not plumbing or electrics.

I'm thinking maybe get an installer in to do the basics, then builders can just add the Honeywell underfloor heating controller when they put in the UFH, and the plumber can put on the right TRVs on the upstairs radiators when he changes those. Although, the wiring doesn't look that complicated for an ordinary electrcian.

I rang the Honeywell Evohome helpline, but the woman didn't know very much and could only tell me general stuff which I've read in the brochure. I rang a Honeywell Connected specialist eight miles away and he said he doesn't travel as far as me. He said maybe he could come round in a couple of weeks if I ring him then. I tried asking him some questions about wiring it in, but all he did was tell me how to lay underfloor heating pipes, which I already know.

The Evohome Shop forum said the installation can only be done by an installer. So I went through Honeywell and ticked four Network Installers closer than eight miles away to contact me. Two days and I've heard nothing.

I just want it done during the building works, not after. So all the boxes are out neatly on walls before decorating and I don't end up wiring in the underfloor heating controller that comes with the system, only to take it out and replace it with an Evohome one straight after, and paying twice.

Is this system really, really that difficult?

I'm hoping someone here can help. Apologies for long post, but I'm struggling to get answers.