The Great British Insulation Scheme caps your upfront cost at roughly £1,200–£1,800 per measure
The Great British Insulation Scheme is a government-funded programme that pays for loft, cavity wall, and solid wall insulation in lower-income and fuel-poor homes. Households that qualify pay either nothing or a heavily reduced price. The government and energy suppliers cover the rest.
The Great British Insulation Scheme caps your cost at roughly £1,200–£1,800 per measure. You may pay nothing if your supplier assesses your home as fuel-poor. Check your EPC band and council tax band first.
- Pay at most £1,200–£1,800 per measure under the scheme cap (Ofgem, 2026).
- Your home must be EPC band D, E, F, or G to qualify.
- Council tax band must be A–D in England or equivalent in Scotland and Wales.
- Each measure must save at least 1,000 kWh per year (DESNZ, 2026).
- Insulation types include loft, cavity wall, and solid wall.
- The Great British Insulation Scheme caps your upfront cost at roughly £1,200–£1,800 per measure
- The scheme targets an energy saving of at least 1,000 kWh per year per installation
- Eligibility hinges on your property’s Energy Performance Certificate band and council tax band
- The step-by-step application process has four clear stages
- Quick numbers key figures in a single table
- You must use an MCS-certified or TrustMark-registered installer
- The Great British Insulation Scheme is a grant that covers most or all of the cost of loft, cavity, and solid wall insulation for eligible homes
The exact cap depends on the measure installed and the supplier administering the grant. The maximum household contribution is set by Ofgem’s scheme rules (Ofgem, 2026). For most measures, you will pay between £1,200 and £1,800 at most. Some households pay nothing at all if the supplier assesses your property as fuel-poor or very low-income (GOV.UK, 2026).
The scheme targets an energy saving of at least 1,000 kWh per year per installation
Each insulation measure installed under the scheme must deliver a minimum modelled annual energy saving of 1,000 kWh. This threshold was set by the Department for Energy Security and Net Zero (DESNZ) to ensure the subsidy delivers measurable bill reductions (DESNZ, 2026).
Typical loft insulation top-up saves roughly 1,000–1,500 kWh per year. Cavity wall insulation saves approximately 2,000–3,000 kWh per year (Energy Saving Trust, 2026). Solid wall insulation can save 3,000–5,000 kWh per year depending on the property type and wall construction. The scheme only approves measures that meet the 1,000 kWh minimum.
Eligibility hinges on your property’s Energy Performance Certificate band and council tax band
Your home must be in EPC band D, E, F, or G to qualify. These are the least energy efficient bands. Your property must also be in council tax band A–D in England, or the equivalent low bands in Scotland and Wales (GOV.UK, 2026).
You do not need to be on a specific benefit. The scheme is built to prioritise low-income and fuel-poor households (Ofgem, 2026). If your home does not meet both the EPC and council tax band criteria, you will not qualify regardless of your income.
The step-by-step application process has four clear stages
Step 1: Check your EPC band and council tax band via your local authority or the GOV.UK checker tool (GOV.UK, 2026).
Step 2: Contact a participating energy supplier. These include British Gas, E.ON, Octopus, OVO, Scottish Power, EDF, and others on the Ofgem list (Ofgem, 2026).
Step 3: The supplier arranges a free home survey to confirm the insulation type and cost cap. The surveyor will inspect your loft, walls, and existing insulation levels.
Step 4: If approved, the supplier schedules installation by an MCS-certified or TrustMark-registered contractor. how to verify an installer’s credentials
Quick numbers key figures in a single table
| Measure type | Typical cost without scheme | Typical household contribution under scheme | Annual kWh saving | Approximate bill saving per year |
|---|---|---|---|---|
| Loft insulation (top-up) | £500–£700 | £0–£200 | 1,000–1,500 kWh | £150–£225 |
| Cavity wall insulation | £1,200–£2,000 | £0–£600 | 2,000–3,000 kWh | £300–£450 |
| Solid wall insulation (internal) | £4,000–£8,000 | £1,200–£1,800 | 3,000–4,000 kWh | £450–£600 |
| Solid wall insulation (external) | £8,000–£15,000 | £1,200–£1,800 | 3,500–5,000 kWh | £525–£750 |
Figures are based on Energy Saving Trust data and DESNZ impact assessments (Energy Saving Trust, 2026; DESNZ, 2026). Your actual savings depend on your home size, heating fuel, and current insulation levels.
You must use an MCS-certified or TrustMark-registered installer
All insulation work under the scheme must be carried out by a contractor registered with the Microgeneration Certification Scheme (MCS) or TrustMark. MCS covers insulation, heating, and microgeneration. TrustMark covers a broader range of home improvements (MCS, 2026; TrustMark, 2026).
You can verify an installer’s certification on the MCS website or TrustMark’s find-a-trade tool. The scheme rules require that your supplier only uses approved contractors (GOV.UK, 2026). If you are offered an installer who is not registered with either scheme, contact Ofgem or your supplier immediately.
The Great British Insulation Scheme is a grant that covers most or all of the cost of loft, cavity, and solid wall insulation for eligible homes
The scheme is a government subsidy, not a loan. It pays for insulation measures that improve your home’s energy efficiency. You do not need to repay the grant, and the installer is paid directly by the energy supplier (GOV.UK, 2026).
The scheme runs until March 2027, so applications are open now (Ofgem, 2026). If you meet the EPC and council tax band criteria, contact a participating supplier to start the process. other government grants for home energy improvements
Frequently Asked Questions
It is a government-funded programme that pays for loft, cavity wall, and solid wall insulation in lower-income and fuel-poor homes. Ofgem sets the rules and caps your contribution at £1,200–£1,800 per measure (Ofgem, 2026).
You pay between £0 and £1,800 per measure, with the cap set by Ofgem (2026). Some households pay nothing if assessed as fuel-poor or very low income (GOV.UK, 2026).
Your home must be in EPC band D, E, F, or G and in council tax band A–D in England (GOV.UK, 2026). You do not need to be on a specific benefit, but the scheme prioritises low-income and fuel-poor households (Ofgem, 2026).
The scheme covers loft insulation, cavity wall insulation, and solid wall insulation (DESNZ, 2026). Each measure must save at least 1,000 kWh per year (Energy Saving Trust, 2026).
Contact your energy supplier or check eligibility via GOV.UK (2026). They will arrange a survey and install the measure if you qualify.
