How to Heat Your Home Efficiently

1: Strategically heat rooms

You don’t need your heat running at full power in every room all day. Instead, heat rooms as and when you need them.

For example, you could:

• Keep bedrooms cool during the day, turning up the heat there a couple of hours before you go to bed.

• Close off unused rooms and turn radiators down there to redirect heat to areas of the house you use.

• Turn the heat down in the kitchen as you cook, taking advantage of the heat produced by the oven or hob.

• Keep children’s bedrooms at higher temperatures at night while turning down the heat in adults’ bedrooms.

To implement zonal heating, you can either close radiator valves or, for more precise control, adjust thermostatic radiator valves. A smart thermostat with zonal control makes heating separate areas easier and can even adjust temperatures in different rooms automatically.

2: Use a smart thermostat

Wi-Fi-enabled smart thermostats give you even greater control over your home heating, with features such as:

If you're wondering why your heating bills are stubbornly high, a smart thermostat can help. Smart thermostats can track your heating use and zero in on inefficiencies, whether it's a child fiddling with a thermostat or a draughty room.

3. Install thermostatic radiator valves

You can set the target temperature by spinning the valve to one of usually five numbers or settings. The higher the number, the higher the room temperature has to be before the boiler switches off: for instance, 3 might correspond to 20°C. The greater control offered by a TRV prevents you from inadvertently overheating a room and makes zonal heating easier, reducing energy use by as much as 40%.^[4]

4. Bleed your radiators

Over time air pockets form in radiators, reducing the ability of heated water to circulate through them and creating cold patches. These patches reduce the surface area through which heat can pass by convection from the radiator to the surrounding air, reducing heating efficiency.

To prevent these air pockets, you should bleed your radiators, letting out water and air through the bleed valve, usually located at the top of the radiator.

You should aim to bleed your radiators at least once a year, in the autumn before you turn your heating on again. However, older heating systems may need to be bled more frequently and you should regularly check radiators for cold patches, especially if your rooms aren’t feeling as warm as they should.

5. Service your boiler

To ensure your boiler is in tip-top shape, you should have it serviced annually, preferably in the autumn before it gets too cold. A typical servicing costs around £100.^[5]

During a boiler service, a Gas Safe engineer will remove limescale and soot buildup from inside the boiler. Both limescale from hard water and soot from fuel combustion can accumulate in the boiler’s heat exchanger and act as insulators, impeding the transfer of heat into water. British Water estimates that limescale buildup alone can reduce a boiler’s efficiency by as much as 12%.^[6] Soot also contributes to the corrosion of the boiler's parts.

The engineer will also check that the boiler's gas pressure, flow rate, and flow temperature are set to maximise its performance. They’ll identify other faults with the boiler which may be making it run less efficiently or could lead to a costly breakdown later.

6. Turn down your boiler’s flow temperature

The flow temperature is the temperature to which the boiler heats water before sending it through the home’s pipes and radiators. While you might assume you should maximise this temperature, boilers actually work more efficiently when the temperature is set a bit lower. Most boilers have their flow temperature set as a default to 75°C-80°C, but the ideal flow temperature for a modern combi condensing boiler is actually around 60°C.

With a lower flow temperature, the water returns to the boiler at a cooler temperature. In a condensing boiler, which most modern boilers are, this maximises condensation within the heat exchanger, enabling the boiler to capture and recycle more heat. More recycled heat means boilers need to use less gas to keep your home warm - around 9% less according to Nesta.^[7]

If your home is adequately insulated, a lower flow temperature won’t have an impact on the temperature of your rooms. Additionally, a lower flow temperature reduces the risk of being scalded by hot water coming out of taps in the kitchen and bathroom.

7. Upgrade your boiler

If your boiler is over 10 to 15 years old and your energy bills are high or your rooms feel cold, you should consider replacing it with a newer model.^[8] While regular servicing can extend the working life of a boiler, all models eventually lose efficiency as they age, especially in areas with hard water.

Additionally, older boilers don’t benefit from the latest technology and standards. For example, boilers installed before 2005 may not have condensing systems which recycle excess heat, and those installed before 2015 weren’t required to be at least 92% efficient (A-rated).^[9][10] Older boilers may also lack heat controls including thermostats, meaning they run continuously until manually turned off, potentially producing more heat than needed.

Some older, less advanced boilers can be just 60% efficient, meaning that 40% of the energy they use isn't converted into heat but is lost.^[11] The Energy Saving Trust says that replacing one of these elderly G-rated boilers with an A-rated modern boiler with heating controls could save you up to £420 on your energy bills annually.^[12]

8. Draught-proof your home

We’ve all had the experience of catching a chill while sitting by a window. Homes can lose up to 20% of their heat through draughts, especially around poorly sealed windows and doors.^[13]

Fortunately, draughts are easy to block up as a weekend project, with supplies available at local DIY shops for just a few pounds. The Energy Saving Trust estimates that draught-proofing measurements can save you up to £85 on your annual energy bills, and will make your home feel more comfortable.^[14]

• !

  A word of caution

  When blocking draughts, make sure you don’t close up necessary sources of ventilation, such as extractor fans in bathrooms and kitchens, wall vents, and trickle vents above windows.

9. Add insulation

Britain’s homes are some of the leakiest in Europe, losing heat up to three times faster than in neighbouring countries.^[15] A big reason for this heat exodus is the poor insulation in our homes, especially in older properties. For example, just 60% of homes in England and Wales have wall insulation judged “average” or better, according to government data.^[16]

If you’re looking to improve your home’s insulation, the best place to start is the loft, where insulation can be added for as little as £300 and pay for itself in energy bill savings in as little as a year.

Beyond the loft, you can look at your home’s walls, where 33% of heat is lost.^[17] Wall insulation is more costly, especially if you have an older house with solid walls, and requires professional installation, but can deliver even bigger savings: up to £500 off your energy bills annually.^[18]

10. Insulate pipes

As heated water travels from your boiler to your radiators, it loses some heat along the way. To reduce this loss, you can easily insulate accessible pipes with foam tubing for as little as £20. The Energy Saving Trust estimates that this insulation can trim around £6 from your heating costs each year.^[19]

You can also insulate the radiators themselves by placing reflector foil behind them, reflecting back into the room heat that would otherwise be lost through the wall.

11. Install or upgrade double glazing

Around 18% of the heat in British homes escapes through the windows.^[20] To slow this heat loss, you should install double glazing. These are windows with two panes of glass, separated by a small gap filled with either dehydrated air or an inert gas that conducts heat more slowly than air. The Energy Saving Trust estimates that replacing single-glazed windows on a semi-detached property with A-rated double-glazed windows could cut your energy bills by £140 per year.^[21]

12% of British homes lack double glazing.^[22] Additionally, around 23% have older double-glazed windows which don’t meet modern standards and have likely become less thermally resistant over time.^[23] That means around a third of UK households could see significant energy savings by upgrading their windows.

12. Consider a heat pump

Even the best gas boilers on the market have a maximum efficiency of 94%. That means that 94% of the fuel they use is converted into heat while 6% is lost.

Other types of heating systems are much more efficient. For example, electric heat pumps can be as much as 300%-400% efficient. For every unit of electricity heat pumps use, they produce three to four times as much thermal energy.^[24]

This incredible efficiency means that heat pumps can be cheaper to run than gas boilers, even though the per-unit cost of electricity is higher than the per-unit cost of gas.^[25] Heat pumps have significantly higher upfront costs than boilers but will eventually pay for themselves through this high efficiency. They’re also responsible for just one-third of the carbon emissions that a natural gas boiler produces.^[26]