This page provides guidance on available grants for cavity wall insulation across the United Kingdom. It outlines key eligibility requirements, explains the application process, and introduces the main government-backed funding schemes. This information is intended for homeowners, landlords, and private tenants who wish to improve energy efficiency and reduce heating costs in eligible domestic properties.

What is Cavity Wall Insulation and Why Is it Required?

Cavity wall insulation refers to the process of filling the gap between the inner and outer layers of external walls with insulating material – commonly mineral wool, foam, or beads – to reduce heat loss.

Approximately one-third of a home’s heat can escape through uninsulated cavity walls. Installing cavity wall insulation significantly reduces this loss, leading to lower annual heating costs and improved indoor comfort.

In practical terms, insulating your cavity walls can:

  • Help save up to £300 per year on heating bills
  • Improve your home’s Energy Performance Certificate (EPC) rating
  • Contribute to national carbon reduction targets

Overview of Government-backed Cavity Wall Insulation Grants

Several grant schemes are available in the UK to support cavity wall insulation for eligible households. These schemes aim to assist low-income and vulnerable residents in upgrading their homes for improved energy efficiency. The main funding routes include:

Each scheme has specific eligibility criteria, application procedures, and funding coverage. Details for each are provided below.

ECO4 Scheme: Energy Company Obligation (2022–2026)

TheEnergy Company Obligation (ECO4) scheme is funded by major UK energy suppliers and overseen by Ofgem. The initiative supports households in reducing energy consumption and carbon emissions through energy-saving improvements, including cavity wall insulation.

Eligibility Criteria:

Applicants may qualify for ECO4 if:

  • The total annual household income is less than £31,000
  • Somebody in the household suffers from a health condition exasperated by the cold
  • The applicant receives one or more of the following means-tested benefits:
    • Income-related Jobseeker’s Allowance (JSA)
    • Income-related Employment and Support Allowance (ESA)
    • Income Support
    • Pension Credit (Guarantee or Savings Credit)
    • Universal Credit
    • Housing Benefit
    • Child Tax Credit
    • Working Tax Credit
    • Child Benefit (subject to income thresholds)

Private tenants may also be eligible, subject to the landlord’s consent.
 Your EPC must also be D and below in order to be eligible for funding

Check your EPC Rating

How to Apply for ECO4 Funding

To apply for funding through the ECO4 scheme:

  • Gather any required documentation, such as confirmation of income, benefits received.
  • Contact Consumer Rights for assistance in determining your eligibility and navigating the application process. You can do this via our online application form.
  • Complete the application form and submit it with the necessary documentation.
  • Consumer Rights will then contact you and arrange an installer for your case.
  • If approved, the installers will schedule a date to assess the property and then carry out the improvements and make your home more energy efficient.

Local Authority Flexible Eligibility (LA Flex)

The LA Flex scheme is an extension of the ECO4 scheme that allows local councils to set their own eligibility rules for energy-saving grants. This enables residents who do not receive qualifying benefits to still access support, further the support for combating fuel poverty.

Other upgrades available through ECO4 and Flex funding:

The Great British Insulation Scheme

The Great British Insulation Scheme is a newer government-backed initiative, administered by the Department for Energy Security and Net Zero. It aims to deliver basic insulation measures, including cavity wall insulation, to households across the UK.
Unlike ECO4, GBIS places additional emphasis on broadening access to middle-income households while prioritising those living in homes with poor energy ratings.

Is Your Property Suitable for Cavity Wall Insulation?

Not all homes are eligible for cavity wall insulation, even with funding approval. The following conditions typically apply:

  • Construction date – Most homes built between 1924 and 2005 have cavity walls suitable for insulation.
  • Wall structure – The external walls must have unfilled cavities at least 50mm wide.
  • Brickwork condition – The masonry must be in good condition with no signs of damp or structural damage.
  • Accessibility – Installers must be able to access external walls safely to perform the work.

If you are unsure whether your home qualifies, an installer will assess these conditions during the initial property survey.

Check Your Eligibility and Start the Process

To see if you may be eligible for funding:

Use our eligibility checker, click here to see if you may qualify for funding. If you are eligible, our team can walk you through the application process.