Posted on 22nd February 2018

What’s the most efficient way to heat a house?

The most efficient way to heat a house is to time your heating for when you need it. If you can, it’s also best to vary the temperature in each room so as not to waste energy warming up space you’re not using. For the best heating, it’s also helpful to have good insulation all around the building to minimise heat loss.

In this guide from Robin Hood energy, we’ll help you to make your heating use as economical as possible with tips on temperature controls, types of heating and insulation recommendations. We’ve designed these tips to help you save money without reducing your comfort – yes, it’s possible to have one without the other!

The most economical way to use central heating

There is some debate over the most economical way to use central heating. Specifically, is it better to leave it on at a lower temperature all the time, or have it on at a higher temperature only when it’s needed? For most people, it’s cheaper to use your heating only when necessary. The energy expenditure require to maintain a steady temperature is greater than people assume, which is what makes the ‘always on’ option less efficient than it seems.

In a theoretical, perfectly insulated house, it would be better to leave the heating on permanently at a lower temperature but, in reality, every house will lose heat. When heat is lost, the central heating has to expend energy to bring the house back to the specified temperature.

In colder weather, the heat loss will be more pronounced, making central heating work even harder. This is because heat loss from the warmer area increases as the difference in temperature between inside and out increases.

Yes, it also requires energy to get a house to temperature when you only want the heating on for a short space of time, but leaving the heating off when you don’t need it saves a lot of energy. Even if you’re in the house most of the day and you need the heating on to stay on for long periods, it’s still worthwhile turning it off at night.

Have as much control over the temperature as possible

If you have the means for more control over your heating, you should make full use of it. Having temperature lower in rooms you’re not currently using will help you save even more energy.
Modern smart thermostats and heating controls can control which rooms are heated at which times, allowing you to warm up the bathroom for your morning shower, then the lounge for your evening TV and your bedroom before you go to sleep.

Even if you don’t have access to a smart system, it’s possible to control the heating more manually with individual room thermostats or radiator valves (which are less precise). While these won’t let you control what time each room is heated, they can help you to lower the temperature in rooms that don’t need central heating as often, like a rarely used spare bedroom or a kitchen that benefits from the oven’s heat.

Whether or not any of these methods are available to you, a simple trick to save energy is to keep each room’s door closed when you want the area to stay warm. This helps because central heating heats with convection, which means radiators create a current of warm air that circulates throughout a room. The bigger the space that needs to be heated, the cooler the air is when it circulates round to be heated again. Closing the door minimises the space, meaning it takes less energy to keep the air at the right temperature.

The cheapest heaters

We’ve only talked about gas-fired central heating so far, but is there a cheaper way to heat your house? There are a few other options available on the mainstream market, including storage heaters, electric heaters and smart versions of both.

However, while these alternatives can be viable for those without access to mains gas, they’re never going to save you money over central heating. According to some estimates, electric heaters – even with the latest and most efficient design – can still use 3 or 4 times the amount of energy that it takes gas central heating to get a room to the same temperature.

Storage heaters are another popular option, especially for those looking to make the most of an Economy 7 tariff. Even in these conditions, however, it can can use twice as much energy to heat a house with storage heaters rather than central heating.

Another advantage of gas heating over electric heaters is that the air tends to stay warmer for longer. While some heaters do heat the air with convection, others heaters warm up the room with radiation, with rays of heat directly warming people and furniture. The problem with these heaters is that their effects tend to fade very quickly once they’re turned off.

Even if you’re not connected to mains gas, there are alternative fuels that you can use to heat your home that can cost less than electric heaters. Gas oil and kerosene are both viable options, though their price can fluctuate and they may not be cheaper than storage heaters on an Economy 7 tariff.

Where is heat lost in a house?

As we mentioned earlier, improving your house’s insulation is a great way to boost the efficiency of your heating. The best insulation options will comfortably save you more than they cost over a year or two. The image below shows you where a typical house loses the most heat.

Diagram showing where heat is lost from a house

How to insulate your house

The walls

Around a third of your house’s heat loss comes through the walls. Most houses built after the 1930s have cavity walls, which mean there’s two walls with a gap (or cavity) in between them. This cavity can be filled with expanding foam insulation that prevents some amount of heat from escaping. In some cases, grants can be obtained that can reduce the up-front cost or even cover all of it.

The roof

Insulating your roof is one of the most significant improvements you can make to your house’s efficiency. The minimum requirement for good insulation is 120mm, but you can get thicknesses up to 270mm if you pay a bit more. If you can afford the extra outlay it’ll be worth it – the thicker the insulation the more heat loss it will prevent. If you plan on being in your property for the long term, roof insulation will comfortably make you back the money that you spent.

The windows

If you have single glazing, the first improvement to make is to upgrade it to double glazing. Even double glazed windows can be upgraded to triple glazing, which will improve your insulation further.

Whether or not you upgrade to double or triple glazing, you can reduce heat loss by closing your curtains at night. This creates a further layer of insulation for the heat to get through. You can even buy insulatory lining for your curtains if you want to increase their efficiency further.

The external doors

Gaps in and around external doors are another heat loss factor. ‘Sausage dog’ draught excluders are one tried and tested solution; they can also be handy for internal doors. There are also products available that can reduce heat loss from letter boxes and pet flaps. For a small price, these keep the opening closed when it’s not in use. It’s a minor improvement, but it can make a big difference in hallways and kitchens.

The floor

You can reduce heat loss through the floor by filling any gaps between the floor and the skirting board with a simple filler. Hard floors are also bad for heat loss, but you can reduce their negative effect by partially covering them with a rug or simply carpeting those areas. If you’ve ever walked barefoot on hard floor, you know how much colder it is than carpet!

Other DIY tricks

Insulation doesn’t have to cost a lot of time or money. There are a few simple tricks you can use to make your heating more efficient:

  • Insulate any exposed pipes – pipes that are exposed to the air lose heat as they take water to your radiators. Simply covering them with insulatory jackets will reduce this issue.
  • Turn the thermostat down 1º – a reduction of a single degree can save you as much as 10% on your heating bills. With the minimum recommended temperature for a thermostat 18o, most of us can turn the heating down by one without any discomfort.
  • Bleed your radiators – if your radiators don’t feel as warm as they should, try bleeding them. You can get a radiator key for £1 or so from most DIY stores. Simply turn it in the radiator until you hear air hissing, then close it again to bleed the radiator and return it to full efficiency.
This guide is not intended to advise you on your personal financial situation. It is providing general guidance only. If you are unsure about a decision or anything mentioned in this guide, you should seek advice from an independent professional.