How to make your home more energy efficient

25 May 2023

As we all look for ways to save money, reducing our energy bills has been at the top of the list for most of us. As the weather gets warmer, it’s a good time to think about how you can get your home prepared for next winter and save some energy.

Creating a more energy efficient home is all about making changes to stop heat from escaping and cold air from creeping in. The result should be a warmer, cosier home.

Not only can save you big money on your bills, as you won’t need your heating on as much; it’s much better for the environment too.

There are lots of things you can do to make your home more energy efficient. Some of them are cheap and others involve a big upfront cost – find the measures that suit your budget.

First, check your Energy Performance Certificate (EPC)

You get an EPC when you buy or rent a home. It’s a document detailing how energy efficient your home is, including projected energy costs. This takes into account usage, fuel costs, and how much carbon dioxide the property emits.

It provides a summary of your home’s energy performance-related features, rating them on a scale ranging from very good to very poor.

Helpfully, the EPC also includes recommendations as to how to make your property more efficient, including the estimated costs of these improvements, and how much you could potentially save by doing so.

Insulate your loft: one of the most cost-effective ways to keep heat in

If you live in a house, then imagine that precious heat rising up through your loft space and into the air, lost forever. A quarter of heat can be lost through the roof if your home isn’t insulated[1]. But loft insulation traps the air inside your house, exactly where you want it.

You may well already have some insulation in your loft, but it may not be thick enough to do the job properly. So, first things first, check your insulation is the recommended depth of 270mm (27cm), and that it covers the whole of your loft space.

If not, buying some insulation could be a worthwhile investment. For a semi-detached house, which currently has no loft insulation, having it installed would cost around £640, but you could then expect to save around £355 per year after that. You’ll quickly make your money back. Better still, follow one of the many video guides available online and do it yourself, saving you on the price of paying a professional installer.

While you’re in your loft, look into insulating any pipes, your water tank and loft hatch too.

Draught proof your chimney (if you aren’t using it)

Log burners have become particularly popular, as people seek ways to heat their homes without resorting to turning on the central heating.

But if you have a fireplace that you don’t use at all, then it’s like having an open hole in your house; warm air will escape out of it and cold air will come in.

So, if you aren’t using it, block it. A common option is a ‘chimney balloon’, effectively an inflatable chimney draught excluder. They are designed to inflate and push against all four walls of the chimney, staying firmly in place, while a small vent allows some airflow, permitting your chimney to breathe (helping to prevent damp).

Limit heat loss from single glazed windows

Your home will also lose plenty of heat through the windows; the government estimates heat loss through windows at an average of 18%[2].

Double glazed windows are typically the best option for keeping warmth in, but having them fitted is expensive. If double glazing isn’t an option, then you can still make changes to limit heat loss and cold air entry at your windows. These include:

Secondary glazing: this ranges from a film you attach yourself, to other DIY kits or even a secondary pane of glass that a professional can install.
Tape or weatherstripping: cheap to buy in DIY stores or online, this comes in a roll and can seal gaps.
Foam sealant: This special foam can be sprayed into gaps around windows or doors.
Thermal curtains: a good pair of thermal curtains can really help to keep your home warm, provided you remember to open and close them!

Don’t let heat escape through doors

Consider any gaps around both external and internal doors that you could fill, seal or block to keep hold of that precious heat.

For the gaps at the bottom, consider a brush or hinged flap draught excluder. Around the edges, foam, brush or strips can help. On external doors, it’s also worth tackling letterboxes (adding a brush) and even keyholes (a cover that drops a metal disk over the gap).

Consider insulating walls, but first find out if they’re cavity or solid

A lot of heat can be lost through your walls too. How you go about insulating them depends on what type of walls you have: houses built before 1920 tend to have solid walls and those built in the last hundred years or so tend to have cavity walls (two solid walls with a space between them).

Solid walls let twice as much heat escape as cavity walls, so it can make a really big difference to insulate them. However, solid walls also cost much more to insulate.

If you’re not sure which type of walls you have, then check the brickwork or measure them:

Cavity walls consist of normal length bricks. And if a wall is more than 260mm thick it probably has a cavity.
Solid walls alternate short and normal-length bricks. If it’s narrower than 260mm it’s likely to be solid.

Insulating cavity walls means paying a professional to spray foam insulation between the two layers. Getting cavity wall insulation will generally cost about £1,200 for a three-bedroom semi-detached home[3].

Insulating solid walls is a much more expensive job: typically around £12,000 for external insulation of £8,500 for internal insulation, depending on the size of your home[4].