7 ways to make your home more energy efficient

05 October 2020 | Matt Mostyn

How efficient is your house

Energy-efficiency. It’s the buzz-phrase for our times, and the gold standard for modern homes. And in the quest to waste less of the stuff, save yourself some money and help care for the planet, there’s plenty that can be done. But before we get into the details, it’s worth defining a bit more clearly what energy-efficiency actually means. 

What is home energy efficiency?

Houses aren’t exactly hermetically sealed! And when the outside world sneaks in, that means you’ll be using more energy to do 2 rather important things: keep warm and stay cool! But with energy efficiency on your radar, it doesn’t need to be this way.

In simple terms, energy-efficiency means doing more with less. So for instance, energy-saving light bulbs create the same amount of light, but use less energy, and waste less heat than old-style light bulbs. 

In the same way, if 2 buildings use the same amount of energy to create heat, the building that can keep in more of that heat is more energy-efficient than the one that lets more escape. You get the idea!

Why’s that so important? Because energy-efficiency manages and limits our levels of energy consumption.  

  • It saves wildlife habitats and helps safeguard the planet
  • It helps to cut down our reliance on planet-polluting fossil fuels
  • And it also helps us pay as little as possible for our energy bills

All of which are compelling reasons to get a handle on how much power and  heating we chew through at home!

So here it is – the 7 best ways we know to make your home an energy-saving haven! See our graphic for the figures at a glance. Or, for further details, see our in-depth recommendations below.

To find out how much electricity an average UK home uses, and how your home compares, read our new guide. 

The 7 best home energy efficiency improvements you can make

 1. Insulate your roof 

Let’s start at the top. You know the old saying that we lose most heat through our heads? Well the same goes for a roof. And just as it’s sensible to pop on a woolly hat when it’s cold, it’s a great idea to take the necessary steps to insulate your loft

Laying down a layer of roof insulation could cost very little. On average, loft insulation for an average semi-detached house costs around £300 – and it could save you as much as  £750 on your bills after 5 years, and about 610kg of carbon per year!

If you receive certain benefits, you might qualify for the Energy Company Obligation Scheme, which can help you cover the cost of insulation. Find out more about the ECO scheme here.

Thinking about converting your loft into an extra bedroom or bathroom? Read our guide to how to pull off an energy-efficient loft conversion.

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2. Insulate your walls

Whether you’ve got cavity or solid walls, filling them with wall insulation could be a very cost-effective way to retain heat in your home and save on your energy bills

Around one third of the heat loss from most homes is through the walls – but cavity wall insulation could save you as much as £165 a year in heating bills1, and 680kg of carbon a year. 

Whether you live in a 1-bedroom flat or a large detached house, you’ll likely recover the installation costs in 5 years or less. That’s purely down to the yearly energy bill savings you’ll make by having a properly insulated home!

If your walls are made of stronger stuff, solid wall insulation can have an even more dramatic impact. That’s because solid walls let twice as much heat escape as cavity walls. And while solid wall insulation can be a more expensive undertaking (depending whether you choose internal or external wall insulation), it’s worth remembering that the savings on your heating bills will also be bigger. In fact, you could save as much as £260 on annual bills and 930kg of carbon a year. 

And if you want some inspiration for energy efficient homes, see our guide to the amazing 'superinsulated' design of Passive Houses.

3. Draught-proof your windows

Insulating your windows is perhaps the easiest and most instantly rewarding way of energy-proofing your home. In winter, a draughty room is far from comfortable, no matter how high your heating is cranked up – so it makes sense to invest in some energy-efficient double-glazed windows. Do this and you could save up to £160 a year on heating bills, and 80kg of carbon. And that’s not to mention the increased levels of peace and quiet you’ll enjoy.

To find more ways to stop draughts getting in and out, check out our complete guide to DIY draught-proofing.

4. Upgrade your boiler 

eco boiler

Inefficient boilers are a major source of expensive home energy bills. Your boiler actually accounts for 55% of your energy bills. That’s more than the rest of your electrical appliances combined! And when they use more energy than they need to run, that’s yet another unnecessary source of excess carbon sneaking its way into the world. 

Boilers are becoming more energy efficient all the time – so if you haven’t had a new boiler within the last 10 years, consider replacing it with a newer model. What’s in it for you? You could actually save up to £205 per year on bills by replacing an old gas boiler with a new A-rated condensing one. For more information, see our guide to the costs of repairing or replacing your boiler.

Plus, switching to a newer or different boiler could be better suited to your home and how you heat it. If you want to install underfloor heating, for instance, a modern condensing boiler will get the best results.

And even if you’re not in a position to replace your old boiler just yet, there are a few other nifty tricks you can try, to make your current one work better. Check out some of our handy hints and tips.

Also, if you're having trouble with low pressure on your boiler, save yourself the hassle and cost of calling out a professional and solve the problem yourself with our easy-to-follow guide.

5. Install solar panels

There’s no denying that installing solar panels can be expensive – but in the long run it’s one of the most effective things you can do to save energy at home. And with the price of solar panels2 being 70% cheaper today than in previous years, it’s actually much more affordable lately.

These days, an average solar set-up will cost somewhere between £2,500 and £8,000 (including installation3), depending on the number of panels and the size of your roof. But we estimate that a 3.5kW panel in southern England will return about £300 to your hip pocket in the first year – and give an approximate 5% rate of return over the 25-year lifetime of the installation. 

Larger solar systems can actually generate as much as 4kWp, which is enough to meet the energy needs of a family of 3 to 4!

And in more good news, there’s new support available to help you pay for energy-efficient upgrades at home, in the form of the Green Homes Grant scheme:

The Green Homes Grant Scheme

In recognition of the importance of good insulation, the UK government has recently announced The Green Homes Grant. It’s part of their effort to reduce carbon emissions and help cut energy bills.

 As part of the scheme, you’ll be able to spend up to £5,000 of vouchers on a myriad of improvements, including:

Check to see if you’re eligible for this brand new scheme.

6. Switch to a better energy plan

One of the easiest ways to cut down your energy bills is to find a better deal – ideally with an energy company that offers renewable energy. With the right deal, not only will you help to lower your bills, but you’ll also be burning through far fewer fossil fuels, which is a win-win for both you and the environment. 

Here at OVO, we now offer 100% renewable electricity as standard. Making the move from 50% to 100% not only means a 24% reduction in total emissions from our members' home energy use, but it’s estimated that we could save 466,706 tonnes of carbon emissions per year4. That's about the same as taking around 177,958 diesel cars off the road for a year5!

7. Keep an eye on the little things

It’s easy to overlook the little things  – but enough small actions can add up to some big changes. So don’t forget to do things like turn off lights when you leave a room, and invest in things like a water-saving shower head and an eco-kettle.

It's also a good idea to bleed your radiators once a year, so they're working as efficiently as possible. Find out how to do it, and why a yearly radiator bleed can bring your heating costs down, with our handy guide.

Even something as simple as turning down the thermostat a degree or 2 can work wonders at reducing your bills without too much impact on your home’s overall temperature. 

If you'd like to use a standlone heater to heat just one room at a time (instead of your central heating), check out our guide to the most energy-efficient heaters out there.

At OVO we’re also doing our bit. We’re currently getting up to all kinds of good stuff to help make UK homes greener and reduce our members’ carbon footprint. The Zero Carbon Heating Trial is just one new initiative that we’ve been picked to run. We’re recruiting 250 homes to take part, and as part of the trial, we’ll be taking out each home’s old gas system and replacing it with a brand new one worth up to £15,000 – all for free! We’ll also carry out other great energy-efficiency measures (like popping in some loft insulation) worth up to £5,000.

We also offer a free online tool, OVO Greenlight. It’s been designed to help OVO members learn more about your carbon footprint, and discover new ways to lighten it. OVO Greenlight also tells you what you can do to start reducing energy waste, without making major sacrifices. Find out more about this handy tool for the energy detectives among us!

For more tips, check out some of our other guides on energy-effiency:

The final word

Every single thing you do can contribute to the whole – no matter how small. Whatever steps you can take, remember this! A well-insulated, energy-efficient home can not only lower your bills and boost your home’s value, it can also lead to a cleaner, greener world for all of us.

Find out more about our energy-efficient plans and switch to OVO today.


We calculated this by first calculating the total carbon emissions that would be caused from our forecasted supply of electricity and gas from 1st October, at 50% renewable electricity as standard. We then calculated how much carbon would be released by the same amount of energy where 100% of the electricity was renewable (renewable electricity is much less carbon intensive). The difference between these is the potential carbon saving.

The average diesel car emits 0.17336 kg carbon per km driven (based on BEIS emission factor). So 466,706,000kg divided by 0.17336 = 269,212,044km. Since the average UK car drives 9,400 miles (15,127.83km) a year, we divided 269,212,044km by 15,127.83 km = 177,958 cars taken off the road for a year.

Sources and references for the infographic: 'How to make your home greener'

1. Calculated based on annual cost savings data provided by the Energy Savings Trust (correct as at September 2020), estimated for an average semi-detached house in England, Scotland or Wales, for the following energy-saving measures:

(1) Loft insulation, saving £150/yr. Estimates based insulating a gas-heated home with a totally uninsulated loft (0mm) with 270mm of loft insulation. Figures are based on fuel prices as of April 2019. Available at:

(2) Cavity wall insulation, saving £165/yr. Estimates based on a gas-heated home. Figures are based on fuel prices as of April 2019. Available at:

(3) Turning off lights when not in use, saving £15/yr. Available at:

(4) Turning down the thermostat by 1 to 2 degrees, saving £75/yr. Typical savings for a typical three-bedroom semi-detached home, heated by gas. Figures are based on fuel prices as of May 2020. Available at:

2. There were 24.41 million dwellings in the UK in 2019 according to Statista ( At £405 savings per dwelling, this scales up to £9.9 billion in energy bill savings nationally. Figures are estimates and do not take into account different types or sizes of dwelling.

3. Calculated based on annual carbon savings data provided by the Energy Savings Trust (correct as at September 2020), estimated for an average semi-detached house in England, Scotland or Wales, for the following energy-saving measures:

(1) Loft insulation, saving 610 kgCO2/yr. Estimates based insulating a gas-heated home with a totally uninsulated loft (0mm) with 270mm of loft insulation. Available at:

(2) Cavity wall insulation, saving 680 kgCO2/yr. Estimates based on a gas-heated home. Available at:

(3) Turning down the thermostat by 1 to 2 degrees, saving 320 kgCO2/yr. Typical savings for a typical three-bedroom semi-detached home, heated by gas. Available at:

(4) Note that an estimate for the carbon saving for turning off lights when not in use was not available from the Energy Savings Trust (as at September 2020) and has been excluded from this total estimate. Total saving: at least 1,610 kg CO2 /year. Based on 24 million typical semi-detached houses in Great Britain, savings calculated at around 40 million tonnes of CO2.

4. An average diesel car emits 0.16844 kgCO2e per kilometre (based on BEIS 2020 emission factors). In the UK, the average car drives 9,400 miles (15,128 km) per year. This equates to 2.5 tCO2e per year for an average diesel car. 39 million tonnes divided by 2.5 tonnes per car is about 15 million cars.

5. The UK's annual carbon emissions in 2019 were 351.5 million tonnes of CO2 (excluding other greenhouse gases) according to provisional BEIS data (published March 2020, available at: 39 million tonnes of CO2 is about 11% of the UK's 2019 carbon emissions.

6. For an average semi-detached home. Estimates based on insulating a gas-heated home with a totally uninsulated loft (0mm) with 270mm of loft insulation. The recommended depth of mineral wool insulation is 270mm, but other materials need different depths. The average professional installation cost is unsubsidised, but prices will vary. Figures are based on fuel prices as of April 2019. Source:

7. Estimated figures, based on installing a new A-rated condensing boiler with a programmer, room thermostat and thermostatic radiator controls (TRVs) in a gas heated home from an older boiler with a programmer and room thermostat. Replacing an old inefficient E-rated boiler with an A-rated condensing gas boiler and thermostatic controls requires an initial layout of around £2,000. The payback comes in the form of £220 a year reduction in your bills as it saves 5,300 kWh or 990 kg of CO2 each year. Savings will vary depending on the size and thermal performance of your home. Figures based on fuel prices as of May 2020.

8. Estimates based on a typical gas-heated home, ranging between a small mid-floor flat and a large detached home. Installation costs will vary depending on the size of the property and windows, material used and choice of installer. Savings are rounded to the nearest £5.

9. The average domestic solar PV system is 3.5kWp and costs around £4,800 (including VAT at 5 per cent).

10. Based on a 307 Wh/mile electric car driving 208.5 miles from London to Manchester, it takes 64 kWh for a one-way trip. 3,700 kWh divided by 64 kWh is around 57 trips.

11. Annual saving/income with the Smart Export Guarantee in London, South East England.

* Stats sourced from The Energy Savings Trust website.

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