GBIS: The Insulation Scheme That Misses the Loft

The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The scheme, which opened in 2023, is supposed to fill the gap left by the closure of the Green Homes Grant. But for most UK homeowners, the question is not whether insulation works. It is whether GBIS works for them.

The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The scheme runs until March 2027, and the government has allocated £1 billion in total. That sounds generous, until you realise the Green Homes Grant had £2 billion and was closed after six months due to poor take-up.

Who qualifies, and who doesn’t

Eligibility is the first hurdle. GBIS is split into two groups: the “low-income group” (households on benefits like Universal Credit or Pension Credit) and the “general group” (homes with an EPC of D, E, F or G, and a council tax band A–D in England, A–E in Scotland and Wales). That second group excludes millions of homes in higher council tax bands, even if they are draughty old Victorian semis. The Energy Saving Trust estimates that around 300,000 homes could benefit from the general group alone. But the total number of homes with uninsulated cavity walls in England is over 4 million, according to the Department for Energy Security and Net Zero.

What it costs a typical 3-bed semi

Assume your home qualifies. The scheme covers the full cost of installation for cavity wall and loft insulation, typically £400–£700 for cavity wall and £300–£600 for loft insulation, depending on access and property size. If you are not eligible, you pay the full cost yourself. For a typical 3-bed semi with uninsulated cavity walls, the annual saving is about £200–£300 on heating bills, according to the Energy Saving Trust. That is not nothing, but it is modest. The payback period is two to three years if you pay for it yourself, assuming energy prices stay near current levels. If you qualify for the free installation, the payback is immediate.

The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. Solid wall insulation, floor insulation, and draught-proofing, all of which can make a bigger difference in older homes, are not included. The government says this is to keep the scheme simple and fast. Critics, including the Energy Saving Trust itself, argue it leaves out the homes that need the most help: pre-1920s properties with solid walls and suspended timber floors.

How to apply, and what to watch for

Applications are handled by energy suppliers. You do not apply directly to government. You contact your supplier, or a registered installer working on their behalf, and they assess your home. The Energy Saving Trust recommends checking your EPC first to see if you are likely to qualify. If you are in the general group, you will need a recent EPC (within the last 10 years) showing a rating of D or below. If you are on benefits, you will need to provide proof.

One warning: the scheme is not a blank cheque. Suppliers have a fixed budget, and once it is spent, the scheme closes to new applicants. That happened with the Green Homes Grant in 2021. If you think you qualify, apply sooner rather than later.

What GBIS will not do is transform your energy bills. It is a stopgap, not a solution. For most households, the real savings come from a combination of insulation, heat pumps, solar panels, and better glazing. Ofgem’s latest figures show that the average household spends about £1,800 a year on gas and electricity. Shaving off £200–£300 is useful, but it is not the 50% reduction that a full retrofit can deliver.