Comment by alkonaut

If I need to dress differently indoors in winter than in summer, I'd consider my house defective. It might be energy efficient to dress a lot more in winter and keep the thermostat at 18 instead of 21 or 22 indoors, but I don't want to. 300mm outer wall insulation, expensive windows, and air heat recycling is something I'll happily invest in to NOT have to lower the thermostat.