The Great British Insulation Scheme is a government grant for cavity wall and loft insulation
The Great British Insulation Scheme (GBIS) is a government programme that provides fully funded or subsidised cavity wall and loft insulation to eligible households in England, Scotland and Wales. It was launched in 2023 and is administered by energy suppliers under obligations set by Ofgem (Ofgem, 2026). The scheme is built to reduce household energy bills and carbon emissions by improving the thermal efficiency of homes.
The Great British Insulation Scheme offers free cavity wall and loft insulation for low-income UK homes with an EPC rating of D to G. Higher-income homes in bands D or E may get a reduced-cost installation through their energy supplier.
- GBIS provides fully funded insulation for low-income homes with EPC D to G.
- Cavity wall and loft insulation are the only measures covered.
- Eligibility requires never having had cavity wall or loft insulation.
- Higher-income homes in EPC D or E get a reduced-cost installation.
- Apply through your energy supplier under Ofgem's framework.
- The Great British Insulation Scheme is a government grant for cavity wall and loft insulation
- Households with an EPC rating of D, E, F, or G and low income are eligible for free insulation
- Households with an EPC rating of D or E and higher income may receive a reduced-cost installation
- Homes in EPC bands A, B, or C do not qualify for the Great British Insulation Scheme
- Quick numbers
- The Great British Insulation Scheme provides cavity wall and loft insulation only, not other measures
- Your energy supplier must install the insulation through an MCS-certified or TrustMark-registered installer
- To confirm your eligibility, check your EPC and contact your energy supplier
The scheme is separate from the Energy Company Obligation (ECO4) but sits within the same regulatory framework. It targets homes that have never had cavity wall or loft insulation, offering a straightforward route to lower heating costs.
Households with an EPC rating of D, E, F, or G and low income are eligible for free insulation
Eligibility is determined by a combination of your Energy Performance Certificate (EPC) rating and your household income. An EPC rating is a measure of how energy efficient your home is, rated from A (most efficient) to G (least efficient).
The scheme targets homes with an EPC rating of D, E, F, or G that have never had cavity wall or loft insulation. Low-income households in these EPC bands qualify for fully funded insulation. Low income is defined as households receiving certain means-tested benefits, such as Pension Credit, Universal Credit, or Income Support, or households with a gross annual income below a threshold set by the Department for Energy Security and Net Zero (DESNZ) (GOV.UK, 2026).
If you meet these criteria, the cost of installation is covered entirely by the scheme, with no contribution required from you.
Households with an EPC rating of D or E and higher income may receive a reduced-cost installation
If your home is in EPC band D or E and your household income is above the low-income threshold, you may still qualify for the scheme. These households receive a contribution toward the cost rather than full funding.
The exact subsidy amount depends on the property’s location and the specific insulation measure. For example, a household in a cold region may receive a higher contribution than one in a milder area. The DESNZ guidance for suppliers sets out the calculation method (DESNZ, 2026). You should contact your energy supplier to find out the exact subsidy available for your home.
Homes in EPC bands A, B, or C do not qualify for the Great British Insulation Scheme
The scheme is explicitly designed for homes with poor energy performance. Properties already rated A, B, or C are considered adequately insulated and are excluded.
If your home has an EPC rating of C but lacks cavity wall or loft insulation, you are still ineligible. The scheme is not intended for homes that already meet a reasonable standard of energy efficiency. Ofgem’s supplier guidance confirms this exclusion (Ofgem, 2026).
Quick numbers
| Measure | Value | Source |
|---|---|---|
| Maximum grant per household (cavity wall) | £1,500 | DESNZ scheme guidance (2026) |
| Maximum grant per household (loft) | £1,000 | DESNZ scheme guidance (2026) |
| Number of measures installed to date (England, Scotland, Wales) | 450,000+ | DESNZ published statistics (March 2026) |
| Typical annual bill saving (cavity wall insulation) | £200–£300 | Energy Saving Trust (2026) |
| Typical annual bill saving (loft insulation) | £150–£250 | Energy Saving Trust (2026) |
| EPC bands covered | D, E, F, G | Ofgem eligibility criteria (2026) |
The Great British Insulation Scheme provides cavity wall and loft insulation only, not other measures
The scheme is limited to two specific measures: cavity wall insulation and loft insulation. It does not cover solid wall insulation, floor insulation, draughtproofing, or heating system upgrades.
If your home needs other improvements, you may need to apply under ECO4 or the Home Upgrade Grant. Ofgem’s guidance on eligible measures confirms this narrow scope (Ofgem, 2026). For example, solid wall insulation is a separate scheme under ECO4, and heat pump grants are available through the Boiler Upgrade Scheme. Learn more about the Boiler Upgrade Scheme and how it compares to GBIS
Your energy supplier must install the insulation through an MCS-certified or TrustMark-registered installer
Installation is carried out by your energy supplier or a contractor they appoint. All installers must be registered with MCS (Microgeneration Certification Scheme) or TrustMark for the relevant insulation measure.
You can check an installer’s certification on the MCS register at mcs-certified.com or the TrustMark website. The installer must provide a 10-year insurance-backed guarantee for the work (MCS, 2026; TrustMark, 2026). This guarantee protects you if the installation fails or causes damage within ten years.
To confirm your eligibility, check your EPC and contact your energy supplier
Your first step is to find your EPC rating. You can check it at epcregister.com for England and Wales or scottishepcregister.org for Scotland. If your EPC is D, E, F, or G and you have uninsulated cavity walls or a loft with less than 270mm of insulation, you may qualify.
Contact your energy supplier directly to apply. The scheme is delivered through suppliers, not a central government portal. If your supplier does not participate, you can switch to a supplier that does, or check the GOV.UK page for a list of participating suppliers (GOV.UK, 2026).
If you are a homeowner and your energy supplier does not offer GBIS, you may still be able to access insulation through ECO4 if you meet the low-income criteria. Read our guide to ECO4 eligibility and how it differs from GBIS
Frequently Asked Questions
The Great British Insulation Scheme is a government programme offering fully funded or subsidised cavity wall and loft insulation to eligible UK households. It is administered by energy suppliers under Ofgem's obligations.
Households with an EPC rating of D, E, F, or G that have never had cavity wall or loft insulation may qualify. Low-income households receiving means-tested benefits like Pension Credit get fully funded installation, as per GOV.UK guidelines.
For low-income eligible households, the scheme covers 100% of installation costs. For higher-income homes in EPC bands D or E, it provides a partial contribution toward cavity wall or loft insulation.
No, the Great British Insulation Scheme is separate from ECO4 but sits within the same regulatory framework. It specifically targets homes needing cavity wall or loft insulation, while ECO4 covers broader energy efficiency measures.
You apply through your energy supplier, which administers the scheme under Ofgem's rules. Check your EPC rating and household income first, as eligibility depends on these factors.
No, the scheme only covers cavity wall and loft insulation. Solid wall insulation is not included, but it may be available under other programmes like ECO4.
