As autumn settles in and energy costs remain a worry for millions, many households are debating whether to keep their heating on low throughout the day or switch it on only when needed.
Money Saving Expert founder Martin Lewis has issued a warning that could make a big difference to winter bills.
He says that while leaving the heating on all day may feel convenient, it could end up costing more, and even create condensation problems in some homes.
Lewis’s warning on heating myths
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Martin Lewis explained that the cheapest way to use heating is to put it on only when you need it, ideally with the help of a timer and thermostat.
“Having the heating on only when you need it is, in the long run, the best way to save energy, and therefore money,” he said.
He also addressed a common misconception: that keeping the heating on low all day prevents heat loss. According to Lewis, in most cases this leads to higher energy usage overall.
He did, however, acknowledge that some heating engineers argue constant low-level heat can reduce condensation, which builds up in walls and increases heat loss once the system is switched off.
Expert backing from the Energy Saving Trust
The Energy Saving Trust has long called the idea of leaving heating on all day a “myth.”
Their research shows that it’s more efficient to heat your home only when required, because keeping radiators running is not the most economical way to use central heating as it increases energy loss over time.
Property type and insulation are key factors. Modern, well-insulated homes may cope better with occasional bursts of heating, while older or draughty houses may need closer attention to prevent damp and condensation.
But the consensus is clear: for most households, intermittent heating remains the most cost-effective approach.
How to heat your home efficiently this winter
According to experts at the Energy Saving Trust, one of the most effective ways to manage costs is by using energy-saving devices like programmable timers or smart thermostats.
These can be set to warm your home when people wake up or return from work, while avoiding wasted energy when the house is empty.
The Trust also recommends keeping thermostats steady between 18°C and 21°C rather than constantly adjusting them, which can lead to unnecessary energy spikes and higher bills.
For homes affected by condensation, a steady background heat may help, but even then, monitoring energy bills closely is essential.
