18th Nov 2022 -

Walls are responsible for around 35% of heat loss in a building, a major concern for any homeowner. Cavity wall insulation can offer an effective solution in most homes built after 1920, but installation can cost as much as £700 in a detached house. A great solution to this for some homeowners is cavity wall insulation grants, a government-run scheme offering enough money to completely cover the cost of cavity wall insulation in your house. Cavity wall insulation involves pumping a layer of insulation into your cavity walls, keeping your home warm and lowering your heating bills.

In this guide from Building Materials Nationwide, we’ll take a look at who is eligible for cavity wall insulation grants, how to apply for them, and whether your house is suitable for cavity wall insulation. A cavity wall insulation grant is not a loan, and you will never have to repay it, saving you hundreds of pounds a year for free.

Can I Get a Grant for Cavity Wall Insulation?

First beginning in 2013, the government's Energy Company Obligation (ECO) scheme requires large energy suppliers to pay for energy-saving measures in British households that meet certain conditions, covering wall and loft insulation. To be eligible for a cavity wall insulation grant, you must either own your own home or get the approval of a landlord if you rent your home. In addition, you must be currently receiving one of the following benefits:

  • Armed Forces Independence Payment
  • Attendance Allowance
  • Carer's Allowance
  • Constant Attendance Allowance
  • Disability Living Allowance
  • Pension Guarantee Credit
  • Income-related Employment and Support Allowance (ESA)
  • Income-based Jobseeker's Allowance (JSA)
  • Income Support
  • Industrial Injuries Disablement Benefit
  • Mobility Supplement
  • Personal Independence Payment
  • Severe Disablement Allowance
  • Tax Credits (Child Tax Credits and Working Tax Credits)
  • Universal Credit

You may also be able to apply for a cavity wall insulation grant if you live in social housing with an EPC rating of E, F, or G. Another possible qualifier is if you are receiving Child Benefit, though this is subject to income thresholds, as shown in the table below.

The number of ClaimantsNumber of Children They Are Responsible For
Single Parent£18,500£23,000£27,500£32,000
Two Parents£25,500£30,000£34,500£39,000

This scheme covers England, Scotland and Wales. If you live in Northern Ireland, you will sadly not be eligible for a cavity wall insulation grant, though there is a scheme called the Northern Ireland Sustainable Energy Programme, which covers some heating upgrades. If you are a landlord looking for a cavity wall insulation grant, you will need to get an eligible tenant to apply.

Insulation at Building Materials Nationwide

Applying for a Cavity Wall Insulation Grant

Applying for a cavity wall insulation grant can be a more difficult process than it needs to be, but thankfully there are some straightforward ways to make enquiries. Rather than applying for a government or council grant through their websites, you will instead need to contact an energy supplier directly. Except for E.on, no home energy provider offers a simple online application, and not all energy providers will offer this service in your area. While there are third-party websites that can act as an intermediary for you, you can apply yourself using the list of contact information for participating energy companies provided by Ofgem. Below is that list, with email addresses or phone numbers for all companies taking part in the scheme.

Energy CompanyEmail AddressContact Phone Number
British Gaseco.referrals@britishgas.co.ukN/A
E (Gas & Electricity) LtdECO@E.orgN/A
E.ON Energy including Npoweralexis.keel@eon-uk.com07790 948592
Ecotricityalan.chambers@ecotricity.co.uk01453 761 380
EDF EnergyECO@edfenergy.com0333 200 5119
ESB EnergyECO@purepla.net0788 037 8170
Octopus Energyeco@octopus.energy0808 164 1088
Outfox the MarketECO@Outfoxthemarket.co.uk0800 103 2702
OVO (Including SSE Energy Services)ECO@ovoenergy.comN/A
Scottish Powerecoenquiries@scottishpower.comN/A
Shell Energy (formerly First Utility and formerly Hudson)eco@shellenergy.co.ukN/A
So Energyeco@so.energy0330 111 5050
The Co-operative Energyeco@cooperativeenergy.coopN/A
The Utility WarehouseN/A0800 781 7777
Together Energy (Retail) LimitedEco@togetherenergy.co.ukN/A
Utilita Energy LtdECO@Utilita.co.uk03452 072 000

Once you have found a company operating in your area, you’ll first need to get your cavity walls surveyed, which will be free. If your home is deemed suitable, and you qualify for the grant, it should completely cover the cost of external cavity wall insulation. There are some cases, depending on the size of your house, where you may have to cover a portion of the cost yourself. This is something that will be told to you before the work starts, and you will have an opportunity to cancel.

Is Your Home Suitable for a Cavity Wall Insulation Grant?

Certain conditions will make your home unsuitable for external cavity wall insulation. If you live in an area with a high level of wind-driven rain, insulating your cavity walls can cause issues with dampness and mould within your house. If the outer walls of your house are cracked or damaged you may also experience issues with cavity wall insulation. 

This is the sort of issue that should be flagged by a surveyor, but it is worth taking into account if you live in the west of Britain, especially Wales, or if your outer walls have visible damage. If this is the case, you will be ineligible for cavity wall insulation and will have to opt for internal or external wall insulation instead, which may not be covered by a government grant. If you have a house with solid walls, you will also need to opt for internal or external solid wall insulation.

Our Selection of Insulation Supplies

At Building Materials Nationwide we offer a wide array of insulation supplies for your home, helping you to conserve heat and save money. If you are looking for internal or external wall insulation products, we offer a wide range of respected brands. We also offer a great range of loft insulation, allowing you to insulate both your walls and loft.