Nearly three-quarters of all UK buildings have cavity walls, yet the Department for Energy Security & Net Zero estimates that up to 29% of these properties lack appropriate insulation. This results in high energy bills and significant residential carbon footprints since heating systems work extra to compensate for the lost heat.

This is where cavity wall insulation comes in. A simple, non-disruptive, and highly effective retrofit that can save up to £405 on energy bills while reducing domestic CO2 emissions by 1.1 tons per year in a detached UK home. To assist fuel-poor and energy-inefficient homes in improving their efficiency, the UK has implemented a main grant scheme that provides free cavity wall insulation. It includes the Energy Company Obligation (ECO4).

This comprehensive guide from Free Boiler Grant will teach you everything you need to know about cavity wall insulation grants, including qualifying criteria and how to apply for these eco-energy grants.

What are the Cavity Wall Insulation Grants in the UK?

The Energy Company Obligation (ECO4) provides cavity wall insulation grants to qualifying households, covering or reducing insulation expenses. These wall insulation subsidies aim to improve the energy efficiency of low-income and fuel-poor houses, keeping with the UK’s ambitious goal of reaching net zero carbon emissions by 2050.

The applicant’s circumstances determine the extent of coverage. Applicants must meet several eligibility requirements to be considered for help, but in most cases, they will receive free cavity wall insulation.

What Are The Benefits Of Cavity Wall Insulation?

Cavity fill insulation provides some of the most significant annual savings regarding energy expenses and domestic CO2 emissions. A detached UK home can save up to £405 in annual energy expenses and reduce its carbon footprint by a whopping 1.1 tons, making this one of the most effective home insulation upgrades available. 

Aside from lower utility expenses, cavity wall insulation has many other advantages and benefits. Here are just a handful of the benefits you could enjoy with this upgrade.

A well-insulated home offers several significant advantages:

1. Insulated homes maintain internal temperatures more effectively, reducing the need for heating and lowering domestic carbon emissions over time, which benefits the planet.
2. Damp and drafty homes can harbor mold and cause structural damage, posing health risks such as respiratory issues and weakened immune systems. Proper insulation promotes a healthier indoor environment with better air quality.
3. Cavity wall insulation, known for its durability, typically requires minimal upkeep when professionally installed. It can last up to 25 years without needing frequent maintenance.
4. Installing insulation can enhance your property’s value in the housing market. A higher Energy Performance Certificate (EPC) rating signals greater efficiency, making your home more attractive to potential buyers or renters.
5. Despite initial costs, cavity wall insulation yields substantial annual savings on energy bills. This means homeowners can recoup their investment within approximately ten years, making it a financially sound long-term decision.

Do You Qualify For Free Cavity Wall Insulation?

To find out if you can get free cavity wall insulation, you must meet two main criteria: 

the grant eligibility rules you’re applying for and living in a home suitable for insulation. In the UK, a scheme offers free cavity wall insulation: the Energy Company Obligation (ECO4). 

Here’s a summary of the basic requirements to qualify for either scheme:

• Home Ownership: You must own or rent from a private landlord. If you rent, you need permission from your landlord to use an insulation grant, whether in private or social housing.
• Income: These schemes prioritize homes with lower incomes. You’re likely eligible if your household earns less than £31,000 gross annually.
• Energy Efficiency: Your home’s Energy Performance Certificate (EPC) rating should be below D (for homeowners) or E (for renters) to qualify for help with insulation.
• Council Tax Band: Homes in Council Tax bands A to D (in England) or A to E (in Scotland and Wales) can also qualify for free insulation through these schemes.
• Government Benefits: If you receive certain government benefits, you’re also likely to qualify. These benefits classify you as part of the low-income group eligible for grants.

These criteria help determine if you can receive assistance with cavity wall insulation, making your home more energy efficient and lowering your heating bills.

Frequently Asked Question

Can you still receive funding for cavity wall insulation?

Grants for cavity wall insulation are still available through the Great British Insulation Scheme (GBIS) and the Energy Company Obligation (ECO4) until March 2026. In any case, applying as early as possible will boost your chances of qualifying on time.

Is it worthwhile to insulate cavity walls?

Insulating hollow walls is an excellent home improvement that provides numerous benefits. Along with reducing your house’s heat loss by up to 33%, cavity wall insulation in a detached home can save up to £405 in energy costs and 1.1 tons in domestic CO2 emissions each year.