All I will say in our defence is that new building regulations are far better in terms of cavity and loft insulation, double-glazing and air-tight door and window seals. My house is a new build and it's toasty warm in winter at my preferred 19C, whereas my partner's house, which is only about 13 years old, is noticeably colder and draughtier. Being a woman, she sets her heating at the predictable 24C or so and yet it doesn't feel as warm all around as mine.