Great British Insulation Scheme (GBIS): Free Home Insulation Explained
GBIS provides free loft insulation, cavity wall insulation, and solid wall insulation to millions of UK households — with two routes: one for any household with a poor EPC rating and another for those on qualifying benefits. Here's everything you need to know.
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GBIS at a Glance
Our 6-question eligibility checker covers GBIS, ECO4, Warm Homes Plan, and more — see all the grants available to your household.
What Is the Great British Insulation Scheme?
The Great British Insulation Scheme (GBIS) is a UK government programme that funds free home insulation for properties with poor energy efficiency ratings. It launched in October 2023 alongside ECO4 and is funded by energy suppliers — meaning the costs are spread across all energy bill-payers, not paid from central taxation.
GBIS has a £1 billion budget and one key difference from ECO4: it has a general route that doesn't require you to receive benefits. If your home has an EPC rating of D or below and is in a lower council tax band, you may qualify regardless of your income. This makes GBIS one of the most accessible UK home energy schemes.
GBIS covers insulation measures only — it does not fund solar panels or heat pumps directly. However, it frequently operates alongside ECO4: if you qualify for ECO4 solar panels, GBIS may fund the accompanying insulation improvements in the same visit, making your solar installation more effective.
The Two GBIS Routes
Best for: Households with poor insulation but not receiving benefits
Best for: Low-income households already claiming benefits
What Insulation Does GBIS Fund?
Minimum 270mm depth. Reduces up to 25% of heat loss in a typical home. The most common and fastest GBIS measure — often installed in half a day. Works by trapping heat before it escapes through the roof.
Injected insulation for cavity-walled homes (typically built between 1930 and 1995). A surveyor checks your walls are suitable first. Can reduce heat loss through walls by 35%. Installed in a few hours.
For older solid-walled homes (pre-1930). Either internal (plasterboard lined) or external (cladding added to outside of wall). More disruptive and expensive — typically means-tested route only.
For properties with a converted loft room. Insulates the sloped ceiling and walls of the attic room. Often missed in standard loft insulation — creates a warm box around the living space.
Underfloor and roof insulation for residential park homes. Park homes lose heat rapidly due to their construction — insulation dramatically improves comfort and reduces heating bills.
☀️ How GBIS Makes Your Solar Panels More Effective
Solar panels generate electricity from sunlight — but if your home is poorly insulated, a significant portion of your heating energy escapes through walls and the roof. Better insulation means your solar-powered electric heating (via a heat pump or storage heaters) goes further, and you export more surplus electricity to earn SEG payments.
If you qualify for ECO4 solar panels, ask your installer whether GBIS insulation can be added in the same package. Many ECO4 installers are also GBIS-registered and can combine both in one visit.
How to Apply for GBIS
Call your energy supplier (British Gas, Octopus, EDF, E.ON, etc.) and ask specifically about GBIS. All large suppliers participate. Alternatively, use the Simple Energy Advice website (simpleenergyadvice.org.uk) to find participating installers independently of your supplier.
Confirm your EPC rating (can be found free at gov.uk/find-energy-certificate) and council tax band (on your council tax bill or at voa.gov.uk). If you receive benefits, have your benefit entitlement letter ready.
A qualified surveyor visits to confirm what insulation your home needs and whether your walls/loft are suitable. For cavity wall insulation, they use a drill test. This survey is free.
An approved, TrustMark-registered contractor installs the insulation. Loft insulation is typically done in a morning. Cavity wall insulation takes a few hours. Solid wall insulation may take several days.
You receive a certificate confirming the insulation installed, the depth/type, and any warranties. Loft and cavity wall insulation comes with a 25-year guarantee. Keep this for your records — it is required if you ever sell your home.
GBIS vs ECO4: What's the Difference?
| Feature | GBIS | ECO4 |
|---|---|---|
| Covers solar panels | No | Yes |
| Covers insulation | Yes — primary focus | Yes — secondary |
| No benefits required | Yes (general route) | No |
| EPC requirement | D, E, F, G + council tax band | D, E, F, G |
| Budget | £1bn | £4bn |
| Can be combined? | Yes — often stacked | Yes |
Frequently Asked Questions
What is the Great British Insulation Scheme (GBIS)?
GBIS is a UK government scheme that provides free or subsidised home insulation through energy suppliers. It runs alongside ECO4 with a £1 billion budget. Unlike ECO4, GBIS has two routes: a means-tested route (similar benefit requirements to ECO4) and a general route open to any household with an EPC of D or below in a lower council tax band. GBIS covers loft insulation, cavity wall insulation, solid wall insulation, room-in-roof insulation, and park home insulation.
Does GBIS cover solar panels?
No — GBIS covers insulation measures only, not solar panels, heat pumps, or other energy-generating technology. If you want solar panels under a government scheme, ECO4 or the Warm Homes Plan are the relevant programmes. However, GBIS and ECO4 can complement each other: better insulation reduces your heating demand, which makes solar panels more effective (more of your solar generation goes towards useful power rather than compensating for heat loss).
What is the difference between the GBIS general and means-tested routes?
The general route is open to any household with an EPC rating of D or below AND in council tax band A–D in England, A–E in Scotland, or A–E in Wales. No benefit requirement applies. The means-tested route has the same benefit eligibility as ECO4 (Universal Credit, Pension Credit, Housing Benefit, etc.) and applies regardless of council tax band — though it prioritises EPC E, F, G properties. The means-tested route also typically covers a wider range of insulation types.
Can I get GBIS and ECO4 at the same time?
In many cases, yes. If you qualify for ECO4 (benefits + EPC D–G), you may receive ECO4 primary measures (like solar panels or a heat pump) AND GBIS insulation through the means-tested route simultaneously or sequentially. In practice, many energy suppliers bundle ECO4 and GBIS measures in a single installation visit, particularly when loft insulation supports an ECO4 solar installation. Your energy supplier will advise on what can be combined.
How do I apply for GBIS?
Contact your current energy supplier directly and ask about GBIS. All major suppliers — British Gas, Octopus Energy, EDF, E.ON, Bulb, Eon Next — participate. You can also use the Simple Energy Advice service (simpleenergyadvice.org.uk) to find participating installers without going through your specific supplier. The process involves a phone or online eligibility check followed by a property survey.
What council tax bands qualify for the GBIS general route?
In England, properties in council tax bands A, B, C, and D qualify for the general route. In Scotland, bands A to E qualify. In Wales, bands A to E qualify. If your property is in a higher band (E, F, G, H in England), you may still qualify through the means-tested route if you receive qualifying benefits. You can find your council tax band on your council tax bill or at voa.gov.uk.
What insulation does GBIS install?
GBIS covers: loft insulation (to minimum 270mm depth — the most common and impactful measure), cavity wall insulation (for properties with unfilled cavity walls, typically built between 1930–1995), solid wall insulation (internal or external, for older solid-walled properties), room-in-roof insulation (for converted lofts/attic rooms), and park home insulation (for mobile homes and park homes). Floor insulation is not covered under GBIS.
Is GBIS still open in 2026?
GBIS was originally scheduled to run until March 2026. The government has indicated that energy efficiency funding will continue under the Warm Homes Plan from 2025 onwards, which subsumes GBIS insulation measures. If you are reading this in 2026 and GBIS has formally ended, equivalent insulation funding should be available through the Warm Homes Local Grant via your local council — contact them directly.
Related Guides & Tools
Sources
Ofgem GBIS guidance (ofgem.gov.uk/gbis); DESNZ Great British Insulation Scheme Order 2023 (legislation.gov.uk); Simple Energy Advice (simpleenergyadvice.org.uk); Energy Saving Trust insulation savings data (energysavingtrust.org.uk).