Can I get cavity wall insulation for free?

Cavity wall insulation is a great way to increase the energy efficiency of your home – and increased energy efficiency means lower energy bills.

Until relatively recently, pretty much everyone was entitled to free cavity wall insulation. However in the last few months things have changed slightly.

The reason for this is that cavity wall insulation installers are paid via a scheme known as ECO. Basically installers get paid an amount per tonne of carbon saved. This sounds a bit ridiculous, but imagine your home uses a certain amount of energy for heating – once the cavity wall insulation is installed, the amount of energy the home uses should drop because there is less heat loss. This saved energy is converted to carbon tonne savings (gas produces CO2 when it burns).

Typically, bigger houses will tend to see greater energy savings when the cavity wall insulation is installed.

  • big house – 10% saving of 45,000kWh of gas is 4,500kWh
  • small house – 10% saving of 17,000kWh of gas is 1,700kWh

This means the amount of funding a larger property gets will tend to be bigger than a smaller property. The same is true when a property has a very old boiler, the savings are greater in these types of home.

ECO rates have dropped

The reason that 100% free cavity wall insulation doesn’t really happen that much any more is that despite the carbon savings being the same as they have always been, the rates the cavity wall installers are paid per tonne of carbon saved have dropped considerably.

Imagine an average cavity wall job costing £1,000 on a 3-bed end of terrace property. Previously, under ECO, the installer would have been paid £1,500 to carry out the install and hence this was 100% free for the homeowner.

Now though, the installer may only be getting £500 from ECO funding, so to cover the rest of the job they need a homeowner contribution.

Homeowner contributions for cavity wall insulation

As we have hopefully explained clearly above, it is rare now for a house to get 100% funding for free cavity wall insulation. Instead, the household will have to make some contribution to get the insulation installed. How much is entirely dependent on the energy performance certificate carried out by a qualified energy assessor – this will all be calculated by the cavity wall installer who will pay for an assessor to carry out this report.

Can you get cavity wall insulation for free?

The difficulty is that the homeowner contribution can vary from house to house; so while your next door neighbour (with a bigger property and more wall to insulate) may only pay £200, you could be given a quote for £500 or more. The key though is to find a good tradesman.

Avoid cowboy cavity wall installers!

Cavity wall insulation is a fantastic energy saving solution and is installed on millions of properties across the UK, however it is does not have a 100% success rate. There are some cavity walls that should not be filled with cavity wall insulation, regardless of whether the energy savings make it an attractive proposition. Properties that are privy to driving rain, or that are located on the coast, should not have cavity wall injected into the void between the skins of brick.

>>> How to avoid cowboy tradesman <<<

Most installers would know not to install cavity wall insulation where it is not suitable. Others, often desperate for work, will not make you aware of the potential issues that may occur further down the line. Unfortunately there are lots of unscrupulous ‘cowboy’ installers out there, so the key is to avoid them and only get good qualified tradesmen.

How to ensure you are getting good quality free cavity wall insulation

The number one thing you need to do to ensure you are getting a highly rated installer is to check whether the company offering you free cavity wall insulation has the Green Deal Quality Mark and PAS2030 processes in place.

PAS2030 is the certification that a company needs to carry out work under ECO scheme and will provide you with the guarantees and piece of mind that the work will be carried out to a high standard. For any company to achieve the PAS2030 mark of quality, they will need to have gone through rigorous testing to ensure their business practises are up to scratch, helping avoid the prospect of cowboys. Unfortunately, even PAS2030 doesn’t completely remove cowboys but it should certainly help!

If you do want to get a decent installer you may wish to ping us through your details below:

We only work with PAS2030 installers and we seek feedback on all our installers ensuring they know what they are talking about!

Interested in learning more about the funding streams within ECO? Read on to learn more!


So ECO works on the energy savings from your home. However just to complicate things, there are three different streams of ECO funding – HHCRO, CSCO and CERO.

ECO is designed to address two areas: one, to help vulnerable members of society meet the rising cost of energy prices by increasing insulation and offering more efficient sources of heat; and two, to help make more expensive measures like insulating solid and hard-to-treat wall insulation more cost effective. HHCRO addresses the first area while CSCO and CERO address the second.

Postcodes and Free Cavity Wall Insulation – CSCO / CERO

Some houses in the UK fall into CSCO / CERO postcodes – these areas are eligible for cavity wall insulation grants. The properties are situated in areas of low income, vulnerable households in rural areas or the properties are identified as hard to ‘hard to treat’ (e.g. thinner cavities).

You can use the link below to see if your property falls into one of these areas:


Currently, around 25% of properties fall into the postcode area, but even if you are in those locations, you may still need to make a contribution depending on the carbon savings resulting from the install of cavity wall insulation.

Qualifying for Free Cavity Insulation through Income – HHCRO

There is another avenue of ECO grant funding based on your circumstances; this is called the ‘Home Heating Cost Reduction Obligation’ (HHCRO), or Affordable Warmth. If the householder is on income support (with related top-ups), receives pension credit or tax credits, you could be eligible for free insulation. In this instance, all that is required is an Energy Performance Certificate (EPC) on the property, and you will also need to provide proof of your entitlements.

Paying for Cavity Wall Insulation

If you know for a fact that you don’t qualify for insulation through any of the means mentioned above, you can still get it installed; and after loft insulation, it offers one of the fastest returns on investment.

    Interested in cavity wall insulation?

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