It’s cheapest to stay in one room with an electric heater or a gas fire
Myth. It might seem obvious that if you are alone in the house and cold, you’re better off sitting next to a heater in one room than turning the central heating on. But this is often untrue. Electricity and bottled gas are both far more expensive per unit than mains gas. Electric fan heaters and portable gas fires are two of the biggest energy guzzlers, and if you have them on for a matter of hours then it’s likely to be cheaper just to turn on your central heating with the radiators on a low setting in the rooms you’re not using.