When we bought our first home, we had Economy 7 heating, which was incredibly expensive, so after our first, massive Winter fuel bill, we learned our lesson and went back to wrapping up in more clothes throughout winter as I'd always done at home, to save on the bills. As our finances improved, we slipped into the habit of wearing T-shirts around the house even in the really cold weather, because we could simply pop the heating on. However, then we bought a house in Spain which we visited at various times of year, and realised on our first winter visit that the Spanish all wear polo neck sweaters with their jeans, and thick padded fleece jackets. Come the evenings we realised why - the temperature drops really quickly out there, and with most homes having tiled floors, and no central heating, you really do NEED to put on extra layers. So after our first night of being freezing cold, we went out the next day and invested in warm sweaters, at which point I suddenly realised that I hadn't worn a polo neck sweater for years, because I simply didn't need to at home. Then the penny dropped that for years I'd been throwing away money, by heating the house rather than my body. I now suffer from a disability which is made much worse by my getting cold, so not only do I wrap up warm when necessary, I have a hot water bottle at my back, then as that cools, and it is replaced, the cooler one gets relegated to my feet helping to keep them cosy too. I also spend a lot of time stuck in bed with my disability, so don't ever need the heating on until early evening, and then it's just on for long enough to take the chill off, before snuggling down to sleep.