The walls of the house proper are solid stone and up to 2 feet thick in places, but the roof void needs insulation in it, and the hatchway really needs to be made bigger first! Mind you if I can squeeze through it... (just a little bit nervous about going up a ladder on a galleried landing...a small galleried landing over the staircase void).
The back lobby is due to be demolished when I eventually get the new extension done. There's an inevitable trade-off due to planning regs on this type of (listed) building, but if I can get a foot or so of rockwool put into the loft, it will be a help. The old heating boiler may be to blame as well, but that is due to be changed in the rebuild. I've dropped the thermostat to around 15C - around 60F, or just below - and the living room fire actually stayed in overnight, so it's not cold in there - apart from the air the fire is pulling in at floor level! It helped that I didn't go to bed till about 2am - kept dozing off in front of the TV.
What the hell did we do when we were kids and nobody had central heating? We're getting soft!