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Cavity wall insulation

Are you looking to insulate your home and become more energy efficient?

Save up to £235¹ on your energy bills with cavity wall insulation.

Get cavity wall insulation

The most effective way of preventing heat loss in your home is with insulation. If you’re eligible as part our grants and schemes, we’ll install cavity wall insulation free of charge, and you don’t need to be an E.ON customer to benefit.

We're a Qualitymark accredited installer, so your insulation comes with an Insurance Backed Guarantee (IBG).

Fill the gaps in your cavity wall and you could save yourself up to £235¹ a year on your heating.

We’ll get most installations done within a couple of hours, depending on the size of your home.

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What is cavity wall insulation?

Beads or fibre are used to insulate cavity walls; both materials provide fantastic energy efficiency properties to help trap the heat you've generated in your home.

Our technicians drill 2cm holes in the mortar joints in the outer wall of your home and inject them with the insulation material using specialist equipment. When the cavity is full, the holes are filled in to match the existing wall.

How to tell the difference between cavity and solid walls

If your home was built after the 1930s, then it’s likely that you have cavity walls. You’ll see a regular pattern of bricks laid on their long sides.

If your home was built before the 1930s, then you'll probably have solid walls. You'll see a regular pattern of bricks laid on their long and short sides.

When we come to see you, our engineer will be able to check what type of walls you have and if they're already insulated.

Cavity wall

Solid wall

What type of walls do you have?

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Is cavity wall insulation messy to install?

Not at all. It’s straightforward and mess-free when done by a cavity wall technician.

Our technicians drill 2cm holes into the outer wall, then inject it with either bead or fibre cavity insulation. Once the cavity is full, the holes are filled in to match the existing wall.

How much does cavity wall insulation cost?

Including installation, the average cost is £2700² for a semi-detached house, this price will vary depending on the size of your home.

Here comes the good part: we may be able to install it for free, depending on your eligibility. We're working in partnership with the government and local councils to deliver free cavity wall insulation to qualifying homes, across the UK through green homes funding schemes. These energy efficiency grants are in place to help homeowners and private renters on a low-income or a means-tested benefit, improve the energy efficiency of their homes.

For more information about cavity wall insulation grants, check out our dedicated page.

Roughly one-third of all the heat created in your home could be lost if your walls aren't insulated. Depending on when your home was built, you could have cavity walls, and if they don’t have cavity insulation, heat is escaping, costing you more in energy bills.

Why not see if you’re eligible and start benefiting from:

Creating a more energy-efficient home
A warmer, more cosy home
Lowering your carbon emissions

Check your eligibility

More about insulation

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Cavity wall insulation grants

Check out and see if you're eligible for a cavity wall insulation grant.

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The Great British Insulation Scheme

You may be eligible for free or discounted home energy efficiency improvements. Find out more and check your eligibility.

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Loft insulation grants

Check out and see if you're eligible for a loft insulation grant.

Are you looking to reduce your energy costs even further?

An air source heat pump could be just what you need to not only reduce your energy costs but also reduce the amount of carbon emissions you produce, building a more sustainable future. And with the boiler upgrade scheme, you can save £7,500³on the cost of installation.

If you’re considering upgrading to an air source heat pump, you’ll need a well-insulated home for the heat pump to work at its most efficient. If your home doesn’t have the correct level of insulation in the loft and walls, heat will escape, making the heat pump work harder and possibly removing any energy savings.

Whether you're thinking of investing in a heat pump or just making your home more energy efficient, insulating your home will help you save on energy costs.