The build

P asks what sort of heat source you've chosen, a gas/leccy boiler, air/ground  source heat pump?

Under floor heating will be hot water heated by electric ( mains / solar combo ). MVHR ( mechanical ventilation heat recovery) and possibly/ probably an  air source heat pump.

Flippin eck I have no idea how that lot would work together? (Says he sitting huddled round a basic wood burner)  It makes you realise how far technology  has moved on from the coal burning era I was brought up in.

The MVHR isn’t really heating as such. It just extracts the heat from the air it sucks out of the house and mixes it with the fresh air it blows into the house. So you’re not losing heat and not getting blasted with cold air. Don’t ask how, not got a clue. Air source heat pump again not really sure how it works. I’ve only had experience of one of the very first models and it was cr@p and it didn’t help that the owner wasn’t using it correctly. So I wasn’t convinced about having one. Apparently they’re much more efficient now and especially if used correctly (not turning on & off like a little electric fire). all clear as mud   .