Hi I live in a small flat that is fully insulated even the walls, the lowest temperature I've seen is 15c, my lounge and bedroom are south facing so only the kitchen and bathroom ar a bit colder, but I can put up with that.
Where as I currently live in a 200 hundred year old house( I say currently because Mrs W has us moving house more often than I get a new bike😂😂😂) Although it was completely renovated 10 years ago, it has 3 floors and 5 bedrooms. So as I said earlier wood burner on for an hour and we are opening the French doors but go in to the downstairs loo and if the heatings not on you might get frost nip on your bum.😱