An easy guide to cavity wall insulation

If your home was built in the last century, its external walls are likely to have a gap (known as a cavity) between their two layers. If left uninsulated, approximately one third of your house's heat will escape through them, which is bad news for your heating bills and the environment.

Cavity wall insulation is designed to plug this gap by effectively acting as a blanket, helping to conserve energy by keeping warmth inside. Getting it installed, which normally takes no longer than a day, will also help to reduce any condensation inside your home.

Checking your home is suitable

First off, you'll need to find out what kind of external walls your property has. If your home was built after 1990, there's a good chance that it has pre-installed insulation. Houses built before 1920 are likely to have solid walls, and properties built in between those dates will probably have cavity walls. You can normally tell which your home has by looking at the external brickwork. If you notice an alternating pattern with varying brick lengths, your home has a solid wall. Bricks following a regular pattern, meanwhile, indicate a cavity wall. And if the cavity is at least 50mm wide you can insulate it.

Saving you money

Installing cavity wall insulation is a great way of saving money. According to the Energy Saving Trust, a semi-detached home could save around £145 per year. Installation at this type of property costs around £475, so the insulation will pay for itself in just over three years. By putting these long-term savings into our budgeting software, you can see exactly how much better off you'll be. Cavity wall insulation is also a long-term investment in terms of comfort, as not only will your home stay cosy in winter, it'll remain cooler during the summer.

Environmental benefits

We've explored how to save money by installing cavity wall insulation, but its benefits go beyond budgeting. A semi-detached home, for example, will make around 600kg's worth of carbon dioxide savings per year – an impressive reduction of a household's carbon footprint. This is particularly significant when you think about the bigger picture: approximately 40% of Britain's carbon dioxide emissions come from easily avoided things like wasting energy.

The installation process

Installing cavity wall insulation is a relatively straightforward process. Although you'll find plenty of DIY guides on the internet, it's really a job for a registered installer. First, they'll drill a number of small holes approximately 1.35m apart in your home's exterior walls. Next, they'll blow the insulation into the cavity. Once these holes are filled to match the wall you'll barely notice them, and can start enjoying the benefits right away.

Despite the benefits of cavity wall insulation, only five million of the UK's 12 million eligible homes have had it installed. So if you're living in one of the seven million properties left, it's definitely worth looking into, so you can start reaping its money-saving and environmental benefits.

Posted by Money Dashboard

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