The perennial winter dilemma of whether to leave the heating ticking over constantly or to switch it on and off has been addressed by Martin Lewis's consumer champion website, MoneySavingExpert. The team has analysed the evidence to provide clear guidance for UK households looking to cut costs without sacrificing comfort.
The General Rule: Off When Not Needed
According to research highlighted by MoneySavingExpert, the common-sense approach often wins. Leaving your central heating running all day usually leads to greater overall heat loss and higher bills. This conclusion is backed by the Energy Saving Trust, which advises that it is more economical to only pay for warmth when you genuinely require it.
The most efficient method for most homes is to use a programmable thermostat. This device allows you to schedule heating for specific times, ensuring your home is warm when you are there and awake, while avoiding wasteful energy use when the house is empty or you are asleep.
When "Low and Slow" Can Be Better
However, the advice is not one-size-fits-all. For homes equipped with modern condensing boilers or heat pumps, a different strategy can be more effective. These systems operate more efficiently when maintaining a steady background temperature, typically around 18 or 19°C.
This "low and slow" method allows them to recover waste heat more effectively than if they are constantly being powered up from cold. The efficiency gain here can sometimes offset the cost of continuous running.
How Your Home's Insulation Changes Everything
A critical factor in this equation is the quality of your property's insulation. Homes with good cavity wall insulation, loft insulation, or underfloor heating are far better candidates for the "low and slow" approach. They retain heat so well that maintaining a constant temperature requires less energy.
In contrast, properties with thinner plasterboard walls and poor insulation will lose heat rapidly, making it significantly more costly to keep them warm all day. For these homes, timed heating is almost certainly the cheaper option.
Some property experts also point out a secondary benefit of constant low heat: it can help prevent condensation and damp. By stopping walls from cooling down completely, you reduce the cycle of moisture being trapped within them, which is a primary cause of mould growth.
Finding Your Personal Best Strategy
Given the variables at play, MoneySavingExpert suggests a practical, trial-and-error method to determine what works for your specific circumstances. Take regular meter readings over two separate weeks with similar outdoor weather conditions.
Try one week using timed heating bursts and another using the constant low-temperature method. Comparing the energy consumption from these two periods will give you a clear, personalised answer on which approach keeps your costs lower.
Ultimately, as Martin Lewis's site confirms, there is no single universal answer to this age-old argument. The most cost-effective choice depends entirely on your heating system type and how well your home is insulated against the cold.
