i know there are some well insulated houses in the U.K. now but so much of the older housing stock is not designed for cold weather. I didn’t fully appreciate this when I first moved to the U.K. because gas was cheap and I had heating on all the time.
I am in a small Victorian mid terrace (pretty much the only housing available in my part of London). Had some renovations including new windows. But still so cold. Fine in mild weather but yesterday I was out all day and didn’t get home until the evening - so heating had been off for 24 hours. It was 13 degrees in my bedroom!