Great British Insulation Scheme

This scheme is now closed to new installations. 

The Great British Insulation Scheme was a government energy-efficiency scheme administered by Ofgem. It was designed to deliver improvements to the least energy-efficient homes in Great Britain to tackle fuel poverty and help reduce energy bills.  

The scheme complimented the Energy Company Obligation (ECO4) scheme, but unlike ECO4’s ‘whole house’ approach, this scheme mostly delivered single insulation measures. 

As well as supporting low-income and vulnerable households, it was also available to those living in homes with an energy performance certificate rating of D to G, and within council tax bands A to D in England and A to E in Scotland and Wales. 

The scheme worked by placing an obligation on medium and large energy companies to deliver measures that result in reduced energy usage. The scheme began in April 2023 and ended in April 2026. 

How did homes benefit from the Great British Insulation Scheme? 

To qualify, properties needed to require energy-efficiency upgrades such as cavity wall insulation. The scheme delivered one insulation measure per home, and upgrades were decided through a retrofit assessment which looked at how making changes to properties could cut energy use and reduce carbon dioxide emissions. In some cases, secondary measures, such as room thermostats or boiler programmers, were available for households in the low-income group. 

This worked by your energy supplier matching you with an assessor who visit your home and decided on the type of measure required. 
  
You must have also either owned your own home or have permission from your landlord – this includes if the property was owned by a social housing provider or management company. 

Who was eligible for the Great British Insulation Scheme? 

The Great British Insulation Scheme was designed to complement the Energy Company Obligation (ECO4) scheme, but it also offered support to a broader range of homeowners and tenants. 

As well as supporting low-income and vulnerable households (through the scheme’s low-income group), this scheme also helped those living in homes within a wider, general group. 

The low-income group was for homeowners or tenants who received at least one of the following benefits: 

• Child Benefit 
• Pension Guarantee Credit 
• Income-related Employment and Support Allowance 
• Income-based Jobseeker's Allowance 
• Income Support 
• Tax Credits (Child Tax Credits and Working Tax Credits) 
• Universal Credit 
• Housing Benefit 
• Pension Credit Saving Credit 

The general group was for those households with properties that have an Energy Performance Certificate (EPC) rating of D to G, and which are within Council Tax bands A to D in England and A to E in Scotland and Wales. 

Local authorities were also able to put forward residents in their areas to energy suppliers, so that they can be offered support under the Great British Insulation Scheme local authority flex.  

It is important to note that eligibility for the Great British Insulation Scheme does not guarantee that an energy supplier or installer would decide to install energy-efficiency measures in your home. 

Read more about the Great British Insulation Scheme. To access all scheme guidance and relevant forms, go to the Contacts, guidance, and resources page. 

What types of insulation were installed under the scheme? 

Both the general and low-income groups were eligible for the following insulation measures: 

• cavity wall (including party wall) 
• loft 
• solid wall 
• pitched roof 
• flat roof 
• under-floor 
• solid floor 
• park home 
• room-in-roof 

Where an eligible insulation measure was installed in owner-occupied premises in the low-income group, certain heating controls - such as room thermostats - would also be allowed, as a secondary measure. 

Higher-cost measures - such as solid wall insulation - would be more likely to need a contribution from the household. 

Did homeowners have to pay to have an energy-efficiency measure installed? 

It was up to the energy companies to determine which retrofit projects they choose to fund, the level of funding they provide, and the retrofit coordinator or installers they choose to work with. 

The level of funding would depend on the measures type, and a number of other factors. In some cases, homeowners may have been asked to contribute to the cost of the installation. The Great British Insulation Scheme was not a grant scheme and as such, different companies or installers provided different levels or types of support towards the installation of energy-efficiency or heating controls. 

Ofgem does not comment on the scale or cost of consumer contributions. Homeowners were encouraged to ‘shop around’ for the best deal to ensure they were satisfied with any offer made. 

Could Great British Insulation Scheme measures be co-funded with other grants or schemes? 

Funding for measures delivered under the Scheme could not be blended with funding from other government schemes or grants. Any measures outside of the Scheme delivered to the same property would have to be installed either before or after all of the Scheme measures were installed. This means non-scheme measures that may impact the properties’ SAP assessment and the post-retrofit SAP assessment. This requirement included, but was not limited to, the following schemes referenced below. 

• Warm Home Discount 
• Home Upgrade Grant 
• Boiler Upgrade Scheme 
• Social Housing Decarbonisation Fund 
• ECO4 
• any other local authority or national scheme that funds energy efficiency measures 

What is the TrustMark scheme and how did it work with the Great British Insulation Scheme? 

TrustMark is a government-endorsed quality scheme providing a high-level of assurance, certainty and protection to consumers who choose to have work carried out in or around their home. 

All installers under the Great British Insulation Scheme had to be TrustMark accredited and have a registration number. You can check these on the TrustMark website. 

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