So we have been in the house about 5 months now and though I'd share a bit about how we are controlling the heating.   As a recap, we have a MBC build house and slab, not the twin wall all pumped cellulose version but slightly less insulating and costly.   Our wall makeup from outside to inside is:   20mm larch hit and miss cladding or Pavex on render board. 50mm battens Some sort of black membrane 9mm OSB 140mm stubs filled with 150mm Warmcell