Hi all, hoping I can get some help on here...

I've got an existing setup of evohome in my house with 8 radiators controlled by HR92 TRVs. I am now having some extension work done and considering having wet UFH installed in 3 new rooms created from the extension. The UFH in each of these three new rooms will need to be controlled independently. I've been reading threads on here about people who have been in a similar situation and I'm just trying to work out if it's worth attempting to control the UFH through evohome or just have it on "dumb" controls.

Main reason I'm debating this is because none of the new rooms will be in use all or most of the time, so we will only need to heat them when we intend to use them and so having the UFH on dumb controls wouldn't be the end of the world. For rooms in the rest of my house which are and will continue to be used more regularly, the HR92s work really well to give me the control I need.

Anyway, as I understand I would need the following:

1 x HCC80R UFH controller - because I would have multiple UFH zones
3 x wireless room thermostat (DT92 or Y87RF) to monitor temperature in each room

It sounds like the wiring between my boiler and the existing BDR91 relay will need amending to incorporate control of the UFH zones. Is that correct? What exactly needs to be done here?

Also, I don't quite understand the equivalent of the HR92 TRVs in the UFH scenario so would appreciate some clarity on that.

Finally, I know this is an automated home forum but I could do with some advice on whether UFH is really the best solution given my expected usage pattern for the extension space. I'm getting the impression UFH is best where you are using the space regularly or all the time and so the system has plenty of time to heat and then you make use of the lasting effects of that heat as you are using the space a lot. In my case, if I will only ever be heating the rooms on occasion when I intend to use them, maybe I'm better off just putting in good ol fashioned rads!

Help would be much appreciated...TIA!