Is it cheaper to keep heating on low all day?

Beautiful tabby kitten sleeps on the radiator near the window

Is it more cost-effective to leave the heating on low all day, or turn it on only when you need it?

How to save money on energy bills is top of most people’s agenda right now, but what’s the best way to heat your home as efficiently as possible? Is it cheaper to have the heating on constantly at a low temperature? Or is it better to turn up the dial as and when you need it?

Here we try to settle the hotly debated issue once and for all, finding out which method’s best for keeping your bills down. Plus we’ll look at some other ways to keep your home toasty and warm.

And if you’re thinking about doing an energy comparison for the best gas and electricity deals, see our article for all you need to know about switching right now. 

Free Look After My Bills money-saving email

Should I keep my heating on low all day?

According to experts, leaving your central heating on low all day isn’t as cost-effective as you may believe. The Energy Saving Trust says: “It’s cheaper to reheat your home than it is to keep it on low all day when you’re not there.”

As you can imagine, whenever you put the heating on ‒ whether that’s on high or low ‒ it uses energy regardless. So if you leave your heating on low all day, you’ll be using energy all day, adding to your energy bills incrementally.

Another factor to consider is the fact that your home always loses heat to the outdoors through the windows, walls and doors – how much depends on how well insulated your home is. This means when the heating is on, your heating system constantly has to work to maintain the temperature you want.

If your home isn’t very energy efficient, it may be worth seeing if you qualify for the Great British Insulation Scheme. You could qualify for free or subsidised insulation if your home is in a lower council tax band, with an energy performance certificate (EPC) rating of D or below.

So what is the best way to heat my home?

It’s generally considered that the most energy-efficient way to heat your home is to use a timer, making sure your home is only heated when you need it.

You can go a step further by installing a smart heating system, or having thermostats for individual rooms. By setting certain areas of your home to heat up at specific times, you’re fully taking control of your usage. Find out what temperature a room should be.

You can also make a significant saving by turning your thermostat down by a degree – so give it a go.

Find out if it’s cheaper to use central heating vs a wood-burning stove.

The dissenting view: keeping heating on low prevents condensation

Not all experts agree that you should heat your home in bursts. It’s been argued that it’s best to keep your boiler on a constant low setting, with your radiator valves set to maximum. This is because, if your radiator frequently swings between hot and cold, condensation can form in the fabric of your walls.

And condensation negatively affects the efficiency of your heating. This is partly because, when you turn on your heating, some of the energy will be used to evaporate the moisture. But also, moisture in your wall cavities means they’re less effective in terms of insulation.

The fancy term for this is thermal conductivity. It means that heat can pass through the walls more easily if there’s trapped moisture. As such, you lose more heat to the outside, rather than keeping it in.

How can you know for sure? Put it to the test

Generally, it’s recommended not to keep your heating on low all day, and to only switch it on when needed. But if your home is well insulated you can test it. 

Well insulated homes lose less heat. So if you leave the heating on low all day, you might not use as much energy to maintain a comfortable temperature.

To test it out, you could try the following – but only if you’re confident your home is well insulated:

  • Before you begin, take a meter reading or check your smart meter. This is your starting point.
  • For one week keep your heating on low all day and take a meter reading at the end of the week.
  • For week two, schedule your heating to come on twice a day and take a meter reading at the end of the week.
  • Now compare both weeks – but allow for a margin of error if one week was warmer than the other.

All being well, you’ll be able to see which option is more cost-effective for your household.

Radiator with heating on low, with two hands on it

Other ways to keep your home warm

Besides timing your heating, there are other ways to keep your home toasty without it costing the earth. We’ve a full round-up in our tips to use less gas and electricity in your home guide, but’s here’s a taster…

Apply for insulation grants

The government is offering various ways to install energy-efficient measures in your home which will keep your bills low. And the best part is the grants will save thousands of pounds on the installation. You’ll need to check if you are eligible though.

Energy grants include the Great British Insulation Scheme, mentioned above. And switching from an inefficient boiler to a heat pump should save you money on your bills over time, so you could also look into the Boiler Upgrade Scheme.

Install a full set of heating controls

These include a thermostat, programmer and thermostatic radiator valves. A spokesperson from the Energy Saving Trust said: “The cost of installation in a typical semi-detached home that doesn’t have any controls is around £580 with annual savings of £180. If you already have a thermostat and programmer, installing thermostatic radiator valves could save £55 a year.”

Get curtains to cover up the windows

It’s a good way of blocking the cold air from outside. You can also get thermal lined curtains which have an extra layer to keep the room well insulated.

Wrap up

This simple trick is all it takes to sometimes avoid putting the heating on: heat the person not the home. During winter, wear warm and comfy clothes like jumpers and hoodies to keep warm.

Of course, if even after that you’re feeling cold, then you should put the heating on.

Use blankets

When relaxing at home, keeping blankets in the living room is also a great way to add another layer of warmth.

Don't block the radiators

If your sofas or coffee tables are blocking the heaters, then it may be worth shifting furniture around so you are not blocking the heat, as this can affect how well the room heats up.

Consider underfloor heating

More energy saving tips