Three live insulation grants can cover the cost of loft, cavity wall, and solid wall insulation in 2026.
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Three live insulation grants can cover the cost of loft, cavity wall, and solid wall insulation in 2026. ECO4 funds full installations for households on qualifying benefits with EPC band D to G homes, running until December 2026. The Warm Homes: Local Grant covers households earning under £36,000 with an EPC of D or below, running until 31 March 2028. ECO4 Flex is the council-administered route for low-income households without benefits. The Great British Insulation Scheme closed to new applications in March 2026.
Eligibility at a glance
Can you qualify for free insulation?
You receive Universal Credit, Pension Credit, ESA, JSA, Income Support, Child Tax Credit or Working Tax Credit
Your home has an EPC rating of D, E, F or G
Your household income is under £36,000 and your home is poorly insulated
You don’t claim benefits but your council runs an ECO4 Flex scheme you qualify for
Free eligibility check
Find every grant your home qualifies for in two minutes.
Three grants currently fund free or subsidised insulation: ECO4, the Warm Homes Local Grant, and ECO4 Flex. The Great British Insulation Scheme closed to new applications in March 2026.
The routes work differently. ECO4 is the largest, administered by every major UK energy supplier under Ofgem regulation, and it pays for full insulation upgrades for households on qualifying benefits. The Warm Homes: Local Grant, part of the government's £15 billion Warm Homes Plan, runs through individual councils and targets households earning under £36,000. ECO4 Flex is the same scheme as ECO4 but uses council-set income criteria instead of benefits.
Every one of these routes can fund loft, cavity wall, and solid wall insulation, with some also covering underfloor insulation and room-in-roof insulation. None of them require you to pay anything upfront if your installer is approved under the scheme.
875,000+
home energy measures funded through ECO4 since 2022, with insulation the most common
If your home is already rated EPC C or above, you generally won't qualify for any of these routes. The schemes target the worst-rated properties because that's where the policy delivers the most carbon and bill savings. Our EPC ratings guide covers how to read your certificate and what counts as a qualifying band.
Who's eligible for free insulation through ECO4?
You qualify if you receive certain benefits, your home is rated EPC D to G, and your property is suitable for the works.
Qualifying benefits
Universal Credit, Pension Credit (Guarantee or Savings Credit), Child Tax Credit, Working Tax Credit, Income Support, Income-based JSA, Income-related ESA, Housing Benefit or Child Benefit (with income limits). Only one household member needs to claim.
EPC band D, E, F or G
Homes already at band C or above don’t qualify. If your last EPC expired more than 10 years ago, an assessor can issue a new one as part of the survey.
Owner-occupied or privately rented
Landlord consent is required for rented properties, but a tenant’s benefit status triggers eligibility. Social housing tenants apply through their housing association instead.
Property suitable for the works
Some homes can’t take cavity wall insulation (timber-frame, single-brick, or steel-frame construction). The installer’s survey confirms what’s technically possible.
Whole-house approach
ECO4 requires homes to reach EPC band C after the works where possible. That means insulation often comes bundled with heating controls, draught-proofing, or a new boiler.
Not sure if you qualify?
The eligibility checker runs your details against ECO4, ECO4 Flex and your council’s Warm Homes Local Grant in 2 minutes.
The whole-house rule is what trips most people up. ECO4 isn't a single-measure scheme any more. If your loft has 100mm of insulation but your walls are uninsulated, the installer is expected to assess the property as a whole and propose the package that gets you to band C. That sometimes means insulation funded alongside a new boiler or new heating controls. It also means the assessor might recommend external wall insulation rather than cavity, depending on construction type.
If you don't claim benefits but your household income is low, ECO4 Flex is your route. Each council sets its own income threshold, typically around £31,000 to £35,000 combined household income. Some councils require an additional qualifying factor: a child under five, a household member with a long-term health condition, or a property in the bottom 25% of EPC ratings locally.
Which insulation grant route applies to your situation?
ECO4 funds loft, cavity wall, solid wall, underfloor, and room-in-roof insulation, plus draught-proofing and heating controls as part of a whole-house package.
The most commonly funded measures are loft insulation top-ups (bringing existing insulation up to 270mm), cavity wall insulation for properties built between 1920 and 1995, and solid wall insulation for older properties without cavities. Solid wall insulation is the most expensive measure ECO4 funds. External wall insulation typically costs £8,000 to £15,000 privately, and ECO4 covers the lot if your home qualifies.
Room-in-roof insulation is the quietly transformative one. If your loft has been converted into a bedroom or office, the sloping ceilings often have minimal insulation behind them. ECO4 funds proper retrofit insulation in these spaces. That can save more energy than a loft top-up because converted lofts have larger heat-loss surfaces.
KEY INSIGHT
Spray foam insulation is not funded under ECO4 and can actually disqualify your home from receiving other measures. Some lenders also refuse to mortgage properties with spray foam in the roof, so be cautious if you've been pitched it by a cold-caller.
What ECO4 doesn't fund: spray foam, blown bead in unsuitable cavities, or any measure on a property already rated EPC C or above. The Energy Saving Trust publishes detailed insulation guidance on what works and what doesn't for different property types.
How much does insulation cost without a grant?
Loft insulation costs £400 to £800 to install privately. Cavity wall is £400 to £1,500. Solid wall is the expensive one at £8,000 to £15,000.
These figures are for a typical three-bedroom semi-detached home with no access issues. Costs scale with property size and complexity. A detached four-bedroom house with a steep pitched roof and limited loft access will sit at the top of the loft range; a small terraced house with easy access sits at the bottom.
The gap between the loft figure and the solid wall figure is why ECO4 prioritises solid wall work for the lowest-rated homes. A solid-walled Victorian terrace at EPC band F probably loses 40% of its heat through the walls. Insulating those walls under ECO4, at no cost to the household, is one of the biggest single interventions available in UK domestic energy policy.
For homeowners who don't qualify for any grant, materials and labour for DIY-friendly loft insulation can be bought for £200 to £400 from any builder's merchant. It's one of the few home upgrades where the DIY option genuinely makes financial sense, provided the loft is empty and the ceiling joists are accessible.
How do you apply for an insulation grant?
Start with the eligibility checker, then book a free assessor visit. The whole process typically takes 4 to 10 weeks from initial enquiry to completed installation.
1
Step 1: Check eligibility
2 minutes
Confirms benefits status, EPC band, and which scheme applies to your postcode.
2
Step 2: Initial assessor visit
1-2 weeks
An approved installer or assessor visits to verify your details, check existing insulation, and confirm what’s technically possible.
3
Step 3: Whole-house assessment
1-2 weeks
Required under ECO4. The assessor proposes the full package needed to reach EPC band C where possible.
For ECO4, you can apply through an MCS-certified installer, an approved comparison service, or directly through an energy supplier. The supplier matching happens automatically based on which one has remaining annual obligation capacity in your area. You don't choose your supplier.
For the Warm Homes: Local Grant, you apply through your council. Coverage varies considerably. GOV.UK's Warm Homes Plan page lists which councils have funding awarded; check yours before applying. Some councils are running tight schemes with quick turnaround. Others have larger budgets and longer waiting lists.
For ECO4 Flex, the route is also through your council. Each council publishes its own eligibility criteria and application form. The advantage of Flex over the main ECO4 route is that you don't need to be on benefits, but the disadvantage is that not every council participates.
Beware of cold-callers and insulation scams
Warning signs to watch for
Legitimate insulation grant installers don’t cold-call, charge upfront fees, or pressure you to sign on the day. If you encounter any of the following, walk away:
Cold-callers or door-to-door installers — Real ECO4 administrators don’t operate this way. Claims you’ve been pre-selected or your street is being surveyed are sales tactics.
Spray foam in lofts — Spray foam isn’t funded under any UK grant scheme and can devalue your property. Some mortgage lenders refuse to lend on homes with spray foam roof insulation.
Upfront fees or admin charges — Genuine ECO4 work involves zero cost to the household. Any fee request is a red flag.
Pressure to sign on the day — Real ECO4 work involves a multi-stage approval process, never an on-the-spot signature.
Claims your home qualifies when it clearly doesn’t — If you don’t claim benefits and your household income is well above £36,000, you don’t qualify for ECO4. Anyone telling you otherwise is misrepresenting the scheme.
The insulation grants market has a particularly bad cold-caller problem because the work is profitable and the targets (older homeowners, lower-rated properties) are often easier to identify from public data. The reputable installers don't need to cold-call. Always check that an installer is registered with the TrustMark scheme before agreeing to any work, and never pay anything upfront for a grant-funded installation.
What if you don't qualify for any insulation grant?
Two routes remain: pay privately at market rates, or check whether 0% VAT relief on energy-saving materials applies to your installation.
ECO4 Flex
OPEN
Best for
Low-income households without qualifying benefits
What it funds
Full insulation package (same as ECO4)
Main catch
Each council sets its own income threshold; not all councils participate
The 0% VAT relief is the most under-used benefit in UK home energy policy. If you're paying privately for insulation, your installer should be applying 0% VAT to the entire installation cost (materials and labour), not just the materials. If they're charging you 20% VAT, challenge it. The relief was introduced in April 2022 and runs to March 2027.
For older homeowners specifically, our insulation grants for pensioners guide covers the combined Pension Credit and ECO4 route that often qualifies even where income looks middle-band on paper.
Can I get free loft insulation on Universal Credit?
Yes, if your home is also rated EPC D to G and your existing loft insulation is below 100mm.
Does ECO4 fund spray foam insulation?
No. Spray foam isn't funded under ECO4 or any other UK grant scheme. It can also create problems with mortgage lenders, some refuse to lend on properties with spray foam roof insulation. If a cold-caller offers you free spray foam, walk away. Stick to mineral wool, blown fibre, or polyurethane board insulation, which are all properly tested and funded under ECO4.
What's the difference between ECO4 and the Great British Insulation Scheme?
ECO4 is the full scheme covering deeper retrofit work for households on benefits with poorly rated homes. The Great British Insulation Scheme (GBIS) was a lighter-touch scheme targeting middle-band EPC homes (D or E) with a wider eligibility net based on council tax bands. GBIS closed to new applications in March 2026. ECO4 continues until December 2026.
How long does it take to get insulation installed under a grant?
From initial enquiry to completed installation, typically 4 to 10 weeks. The eligibility check takes 2 minutes. The assessor visit and supplier or council approval take 4 to 6 weeks. Loft and cavity wall installation are usually one day on site; external wall insulation takes 1 to 3 weeks depending on property size.
Can tenants apply for insulation grants?
Yes, but the route depends on tenure. Private tenants on qualifying benefits can trigger ECO4 eligibility for their landlord's property, though landlord consent is required for the works. Social housing tenants apply through their housing association, which has its own decarbonisation budget. Private tenants whose landlords refuse consent have no direct route through ECO4.
Will insulation actually improve my EPC rating?
Yes, often by one or two bands depending on what's installed. Cavity wall insulation alone typically improves a rating by one full band. Combined with loft insulation and heating controls, two band improvements are common. The ECO4 whole-house approach is specifically designed to get qualifying homes to band C wherever possible, so most ECO4-funded packages produce a measurable EPC uplift.