I’m working on an MBC PH project atm and we’ve had this chat. Defo going to install UFH on the FF, but I’ve spec’d it for only 70-80% of each of the room floor areas to be heated, due to the anticipated minimal heating requirements.
I’ve asked MBC to make some changes to the upstairs construction to allow me to get alu spreader plates in as quickly as possible when they get up to wall plate height. Planning that to happen on a Thursday / Friday so we can ask MBC to stand down so the install of all the ff UFH can be done over a long (bat-shit crazy) weekend……I am well aware that MBC will be champing at the bit again at 07:00 on the Monday morning(!!) so I’ve got a few good people lined up to help out as it’s quite a big (400m2 iirc) house.
After the slab detailing for ductwork, my next joy is going through heating and cooling / plant etc, and have planned some fan coils to blast the FF landing (full height, fully glazed gallery aspects each side) to scavenge unwanted stagnant heat away.
Some powered Velux windows will step in early for a bit of passive purge, so the reliance on cooling or more specifically cooling under duress is mitigated against at the design level.
Hopefully it all works at the end or I’ll have to move house. Lol.