The cost of keeping warm in an old house

Just over a week ago my wife and I were pacing the bare wooden floor of our
sitting room wearing hats and scarves. It was -2C outside and, clearly, not
much warmer inside. We had a fire lit and the central heating going full
blast, but did it make any difference? No. As we shivered, our thoughts
turned to the scene in Withnail and I in which Withnail, overwhelmed
by the intense cold of Monty’s farmhouse, remarks that they “might as well
sit round a cigarette”.