Money Saving Expert Martin Lewis has confirmed the minimum temperature households should set their heating to this winter. On the energy bills special of The Martin Lewis Money Show Live, broadcast on ITV1 and ITVX, he set out the official guidance for healthy adults.
WHO guidance and the one degree challenge
Lewis said the World Health Organisation (WHO) advises that a healthy adult can set the thermostat at 18 degrees C. He noted that most households run their heating higher, which is more expensive, especially with energy bills forecast to rise by 24% in January.
He encouraged households to try dropping their thermostat by one degree, saying this small change can save as much as 7% on energy bills. Lewis said: "Take my one degree challenge. It doesn't sound very much."
Advice for vulnerable groups
Lewis acknowledged that people with medical conditions or older people may need a higher temperature. He added: "Obviously if you've got a medical condition or older people, you'll want it to be higher. But if you were to drop from say, 21C to 20C, that could cut your heating bill by 7%."
He also advised against turning the thermostat up when it is colder outside, explaining that the thermostat's job is to keep the house at a set temperature.
NHS backing
The guidance is supported by the NHS. In a paper titled 'Minimum temperature threshold for homes in winter', the NHS said indoor temperatures of at least 18C pose minimal risk to the health of a sedentary person wearing suitable clothing. It warned that below 18C, negative health effects may occur, such as increases in blood pressure and the risk of blood clots, which can lead to strokes and heart attacks.
