The Great British Insulation Scheme offers a fixed discount, not a full grant. That makes it worth it only for specific households
The Great British Insulation Scheme (GBIS) is a government programme that provides a fixed discount toward a single insulation measure per eligible home, typically loft or cavity wall insulation. Unlike ECO4, which can fund multiple measures, GBIS is a one-off intervention designed for lower-cost, faster installations.
The Great British Insulation Scheme is worth it only if your home has an EPC rating D–G and uninsulated loft or cavity walls. It provides a fixed discount of £1,500–£2,000, but you may need to pay a small contribution if costs exceed the cap.
- Check your EPC rating D–G and council tax band A–E to qualify.
- Expect a fixed discount of £1,500–£2,000, not full cost coverage.
- You may pay a small contribution if installation costs exceed the cap.
- Only one measure per home: loft, cavity wall, or solid wall insulation.
- The installer selects the measure, not the homeowner.
- The Great British Insulation Scheme offers a fixed discount, not a full grant. That makes it worth it only for specific households
- Eligibility for the Great British Insulation Scheme depends on your property’s Energy Performance Certificate rating and council tax band
- The scheme covers one of three insulation types, and the installer decides which is best for your home
- Quick numbers typical savings, costs, and installation times for the Great British Insulation Scheme
- The Great British Insulation Scheme is worth it if your home has no existing insulation and you cannot afford full private installation
- To use the Great British Insulation Scheme, you must use an MCS-certified installer registered with your energy supplier
- The scheme runs until March 2027, so you need to apply before the deadline to secure funding
Homeowners must pay a small contribution if the government’s cost cap is exceeded, so the “worth” depends on your property’s current insulation level and the installer’s quote. The scheme covers most of the cost but not all of it, meaning you may still need to pay a portion if the installation price is high (DESNZ, 2026).
Eligibility for the Great British Insulation Scheme depends on your property’s Energy Performance Certificate rating and council tax band
Your home must have an Energy Performance Certificate (EPC) rating of D, E, F, or G (the lowest efficiency bands) to qualify. You must also be in council tax bands A–E in England, or A–G in Scotland and Wales, though some exceptions apply for low-income households (DESNZ, 2026).
The property must have uninsulated cavity walls or an uninsulated loft (less than 60mm of existing insulation) to be considered for the measure. If your home already has adequate insulation, you will not qualify, regardless of your EPC rating or council tax band.
The scheme covers one of three insulation types, and the installer decides which is best for your home
Loft insulation, cavity wall insulation, and solid wall insulation (internal or external) are the three eligible measures, but not all homes qualify for all three. The installer will conduct a survey to determine which measure can be installed within the government’s cost cap, typically £1,500–£2,000 per property (Ofgem, 2026).
Homeowners cannot choose the measure themselves; the installer selects the one that will deliver the most cost-effective energy saving for the property. This means you may not get the insulation type you prefer, but the decision is based on what will reduce your bills most effectively.
Quick numbers typical savings, costs, and installation times for the Great British Insulation Scheme
| Insulation type | Typical annual energy bill saving (£) | Average homeowner contribution (£) | Typical installation time (hours) | Estimated U-value improvement |
|---|---|---|---|---|
| Loft insulation (top-up from 60mm to 270mm) | £100–£200 | £0–£50 | 4–6 | 0.16 to 0.11 W/m²K |
| Cavity wall insulation | £200–£300 | £0–£100 | 2–4 | 0.50 to 0.30 W/m²K |
| Solid wall insulation (internal/external) | £300–£500 | £0–£200 | 8–16 | 0.45 to 0.25 W/m²K |
Figures are based on a typical 3-bed semi-detached home. Homeowner contribution is typically £0 for most, but can be up to £200 if the installation cost exceeds the government cap (Energy Saving Trust, 2026; DESNZ, 2026).
The Great British Insulation Scheme is worth it if your home has no existing insulation and you cannot afford full private installation
The direct answer to “is the great british insulation scheme worth it” is: Yes, if your home is uninsulated and you are in the eligible EPC and council tax bands, because the scheme covers the majority of the cost. It is not worth it if you already have good insulation, if your home needs multiple measures (ECO4 is better), or if you can pay for private installation with a payback period under 3 years (Ofgem, 2026).
The scheme’s value is highest for low-income households in energy-inefficient homes, where the savings on bills can offset the small upfront contribution within one winter. For households with an EPC rating of D or above, private installation may offer a faster return on investment.
Compare ECO4 vs GBIS eligibility and funding differences
To use the Great British Insulation Scheme, you must use an MCS-certified installer registered with your energy supplier
All installations under GBIS must be carried out by an installer who is certified under the Microgeneration Certification Scheme (MCS) for insulation work. You cannot choose your own installer; you must go through a participating energy supplier (e.g., British Gas, EDF, Octopus) who will assign an approved contractor (MCS, 2026).
The installer must also hold TrustMark accreditation for consumer protection, and the work must comply with Building Regulations (TrustMark, 2026). This ensures the installation is done to a professional standard and that you have recourse if something goes wrong.
The scheme runs until March 2027, so you need to apply before the deadline to secure funding
The Great British Insulation Scheme is funded until 31 March 2027, with no announced extension as of early 2026. Applications can take 4–8 weeks from initial contact to installation, so applying early in 2026 is recommended to avoid last-minute rushes (DESNZ, 2026).
If the scheme ends before your installation is completed, you may be left with a partial installation and no further funding. Check with your energy supplier about their current application queue times before committing.
How to check your EPC rating online for free
Frequently Asked Questions
The Great British Insulation Scheme is a government programme offering a fixed discount toward one insulation measure per eligible home, typically loft or cavity wall insulation. Ofgem administers the scheme, which targets lower-cost, faster installations.
You need an EPC rating of D, E, F, or G and be in council tax bands A–E in England or A–G in Scotland and Wales. The property must have uninsulated cavity walls or less than 60mm of loft insulation, as per DESNZ rules.
The scheme covers up to £1,500–£2,000 per property, but you may need to pay a contribution if the installation cost exceeds this cap. The exact amount depends on the installer’s quote and your property’s needs.
No, the installer decides which single measure to install after a survey, based on what fits the government’s cost cap. You cannot choose between loft, cavity wall, or solid wall insulation yourself.
No, GBIS offers a one-off fixed discount for one measure, while ECO4 can fund multiple measures per home. GBIS is designed for simpler, faster installations for lower-energy-rated homes.
