Home Insulation Grants 2025: Complete Guide to GBIS & ECO4 Free Insulation

UK homeowners can access thousands of pounds worth of free insulation through government schemes in 2025. The Great British Insulation Scheme (GBIS) and ECO4 provide fully funded upgrades to millions of households, reducing energy bills by £300-£600 annually while improving comfort. This comprehensive guide explains both schemes, compares eligibility, and shows you how to claim your free insulation.

Understanding the Two Main Insulation Schemes

The UK government funds insulation improvements through two complementary schemes with different focuses and eligibility criteria. Understanding both helps you determine which scheme (or combination) offers the best support for your home.

Great British Insulation Scheme (GBIS)

Launched in October 2023 and running through March 2026, GBIS specifically targets insulation measures for homes rated EPC D or below. The scheme aims to insulate 300,000 homes, with funding allocated on a first-come, first-served basis.

Key features:

• Focuses exclusively on insulation (loft, cavity wall, room-in-roof)
• Available to households with income below £36,000
• No benefits requirement for those in council tax bands A-D
• 100% funded for most eligible households
• Can be combined with ECO4 for comprehensive upgrades

ECO4 (Energy Company Obligation)

Running from April 2022 through March 2026, ECO4 takes a "whole house" approach, addressing multiple energy efficiency measures including insulation, heating, and renewable energy in a single project.

Key features:

• Covers all insulation types plus heating system upgrades
• Prioritises benefits recipients and low-income households
• Mandatory for major energy suppliers to fund
• Targets properties with EPC ratings of E, F, or G primarily
• Aims to achieve EPC rating of C where feasible

GBIS Eligibility: Who Qualifies for Free Insulation?

The Great British Insulation Scheme uses a tiered eligibility structure based on council tax band and household income.

General Route: Council Tax Bands A-D

If your property is in council tax band A, B, C, or D, you automatically qualify for GBIS if:

• Your household income is below £36,000 per year
• Your property has an EPC rating of D, E, F, or G
• The recommended insulation measures are applicable to your home

This route is designed for working households who don't receive benefits but still face fuel poverty due to poor home insulation.

Low Income Route: All Council Tax Bands

If you receive means-tested benefits, you qualify regardless of council tax band:

• Universal Credit
• Income Support
• Income-based Jobseeker's Allowance
• Income-related Employment and Support Allowance
• Pension Credit
• Working Tax Credit
• Child Tax Credit
• Housing Benefit

What Insulation Measures Does GBIS Cover?

GBIS funds three primary insulation types:

• Loft insulation: Topping up to 270mm depth (worth £400-£800)
• Cavity wall insulation: Filling wall cavities with insulating material (worth £800-£2,000)
• Room-in-roof insulation: Insulating converted loft spaces (worth £2,500-£4,500)

Notably, GBIS does not cover solid wall insulation, which falls under ECO4 due to higher costs and complexity.

ECO4 Eligibility: Comprehensive Support for Energy Efficiency

ECO4 offers broader support than GBIS, covering all insulation types plus heating system upgrades. Eligibility is similar but with nuanced differences.

Benefits-Based Route

If you or anyone in your household receives qualifying benefits, you automatically qualify:

• Universal Credit (with household income below £31,000)
• Pension Credit (Guarantee or Savings Credit)
• Income Support
• Income-based JSA or ESA
• Working Tax Credit or Child Tax Credit
• Housing Benefit
• Warm Home Discount recipient
• Child Benefit (with income below £31,000)

ECO4 Flex: Income-Based Route

Local authorities can refer households living in fuel poverty who don't receive qualifying benefits:

• Household income below £36,000 (£40,000 in some areas)
• Property rated EPC D, E, F, or G
• Vulnerable to fuel poverty (assessed by local authority)

What Does ECO4 Cover?

ECO4's comprehensive approach includes:

All Insulation Types

• Loft insulation: Up to 270mm depth
• Cavity wall insulation: Standard and hard-to-treat cavities
• Solid wall insulation: External or internal (worth £8,000-£20,000)
• Room-in-roof insulation: Converted loft spaces
• Underfloor insulation: Suspended timber floors
• Park home insulation: Specialist solutions for mobile homes

Heating System Upgrades

• Boiler replacement: Upgrading inefficient boilers (15+ years old)
• First time central heating: For homes without heating systems
• Storage heaters: Modern, efficient electric heating
• Heating controls: Smart thermostats, TRVs, programmers

Additional Measures

• Draught proofing
• Hot water cylinder insulation
• Solar panels (in some whole-house approaches)

GBIS vs ECO4: Which Scheme Should You Apply For?

The good news: you can potentially access both schemes for maximum support. Here's how to decide your approach:

Decision Framework

Choose GBIS if:

• You only need loft or cavity wall insulation
• Your home has cavity walls (post-1920 construction)
• Your heating system is relatively modern and efficient
• You want a quick, straightforward installation

Choose ECO4 if:

• Your home has solid walls needing insulation
• Your boiler is over 15 years old or inefficient
• You need multiple improvements (insulation + heating)
• Your property is rated E, F, or G and needs comprehensive work

Access both if:

• You qualify for both schemes
• You need both insulation and heating upgrades
• Your home requires solid wall insulation plus other measures

How Much Can You Save?

The financial impact of insulation improvements is substantial, with typical households saving hundreds of pounds annually on energy bills.

Annual Savings by Measure

Combined Savings Examples

Example 1: Post-1920 Semi-Detached (GBIS)

• Loft insulation top-up: £250/year saving
• Cavity wall insulation: £390/year saving
• Total annual saving: £640
• 10-year savings: £6,400
• Installation cost covered: £1,200 (fully funded by GBIS)

Example 2: Pre-1920 Terrace House (ECO4)

• External wall insulation: £555/year saving
• Loft insulation: £300/year saving
• Boiler replacement: £450/year saving
• Total annual saving: £1,305
• 10-year savings: £13,050
• Installation cost covered: £15,000+ (fully funded by ECO4)

How to Apply for Free Insulation

The application process for both GBIS and ECO4 follows similar steps and is managed through registered installers rather than government departments.

Step-by-Step Application

1. Check Your Eligibility: Use our grant finder tool to quickly determine which schemes you qualify for. You'll need to know your EPC rating (or arrange for assessment).
2. Gather Documentation: Prepare proof of benefits, income, address, and EPC certificate. If you don't have a current EPC, the installer can arrange one.
3. Contact a Registered Installer: Find TrustMark-registered installers approved for GBIS/ECO4 delivery. Avoid cold-calling companies and verify credentials.
4. Home Survey: A qualified assessor visits to evaluate your property's insulation needs, construction type, and suitable measures. This takes 30-60 minutes.
5. Receive Improvement Plan: The installer creates a comprehensive plan detailing recommended measures, expected energy savings, and EPC rating improvement.
6. Confirm Eligibility: The installer verifies your eligibility with the funding scheme and confirms 100% funding (or any small contribution required).
7. Schedule Installation: Once approved, installation is scheduled. Timelines vary from 1 day (cavity wall) to 2-4 weeks (solid wall insulation).
8. Post-Installation Checks: After completion, the work is inspected to ensure it meets Building Regulations and scheme requirements. You receive insurance-backed guarantees (typically 25 years).
9. Updated EPC: An updated EPC is issued showing your improved rating and reduced energy costs.

Timeline Expectations

• Initial assessment: 1-2 weeks from application
• Approval: 1-3 weeks
• Installation scheduling: 2-8 weeks (depending on measure complexity and demand)
• Installation completion: 1 day to 4 weeks (varies by measure)
• Total timeline: 6-14 weeks from application to completion

Avoiding Insulation Grant Scams

Unfortunately, scammers target government grant schemes. Protect yourself with these precautions:

Red Flags to Watch For

• Upfront payments: Legitimate schemes are free for eligible households. Never pay for surveys or applications
• Cold calls/doorstep sales: Reputable installers don't use aggressive sales tactics
• Pressure to sign immediately: Take time to verify credentials and read documents
• Too good to be true claims: "Government paying £10,000 for everyone" style promises
• Lack of credentials: No TrustMark registration, CIGA, or company details

Verification Checklist

Before proceeding with any installer, verify:

• TrustMark registration (check on trustmark.org.uk)
• CIGA membership for cavity wall insulation
• SWIGA membership for solid wall insulation
• Insurance-backed guarantees (25 years minimum)
• Physical business address and landline number
• Reviews on independent sites (Trustpilot, Google)

What Happens After Installation?

Once your insulation is installed, you'll immediately begin experiencing benefits, but there are a few post-installation steps to be aware of.

Immediate Benefits

• Warmer home: Noticeable improvement in comfort within days
• Lower bills: Savings appear on your next energy bill (within 1-3 months)
• Improved EPC: Rating improvement opens doors to further grants
• Reduced condensation: Warmer walls reduce damp and mould risks

Guarantees and Protection

All GBIS and ECO4 installations come with:

• 25-year guarantee: Insurance-backed protection for insulation performance
• Workmanship warranty: Coverage for installation defects
• Complaints process: Route to resolution through TrustMark if issues arise
• Post-installation support: Installer should provide ongoing advice

Next Steps: Further Improvements

After insulation, consider complementary upgrades:

• Heating upgrade: If ECO4 covered insulation only, ask about boiler replacement
• Heat pump: Well-insulated homes qualify for £7,500 Boiler Upgrade Scheme
• Solar panels: Generate renewable electricity (0% VAT applies)
• Smart controls: Thermostats and TRVs to maximize insulation benefits

Scheme Deadlines and Future Support

Both GBIS and ECO4 currently run until March 2026, but future support is expected.

Should You Apply Now or Wait?

Apply as soon as possible if you're eligible because:

• Funding is first-come, first-served
• Demand increases as awareness grows
• Installer availability becomes constrained near deadlines
• Every month without insulation costs £30-£100 in wasted energy
• Future schemes may have different eligibility or reduced funding

What Happens After March 2026?

The government has committed to continuing energy efficiency support beyond 2026. ECO5 or successor programmes are expected to be announced in 2025, likely maintaining support for fuel-poor households. However, specific eligibility and funding levels are uncertain, making current schemes attractive.

Maximising Your Grant Benefits

To get the most from GBIS and ECO4:

1. Get an EPC first: Know your starting point and which measures are recommended
2. Accept the full package: Don't cherry-pick measures. The comprehensive approach delivers best results
3. Combine schemes: Use GBIS for simple insulation, ECO4 for complex measures
4. Plan future improvements: After insulation, your improved EPC opens access to other grants
5. Verify all credentials: Protect yourself by thoroughly checking installer qualifications
6. Keep all documentation: Certificates, guarantees, and EPCs are valuable for future sales/rentals

Take Action Today

Insulation grants represent extraordinary value - thousands of pounds of improvements at no cost for eligible households. The energy savings begin immediately and compound over decades, while comfort improvements enhance daily life quality.

With both GBIS and ECO4 available until March 2026 but funding allocated first-come, first-served, delaying your application means risking missed opportunities. Every month without insulation is money wasted on heating an inefficient home.

Whether you're a homeowner looking to reduce bills, a landlord meeting regulations, or simply someone who wants a warmer, more comfortable home, these schemes provide accessible pathways to meaningful improvements.