Understanding the Boiler Upgrade Scheme
A complete guide to the UK government’s flagship programme helping homeowners transition to cleaner, more efficient heating systems
What is the Boiler Upgrade Scheme?
The Boiler Upgrade Scheme provides upfront capital grants to property owners in England and Wales who want to replace fossil fuel heating systems with low-carbon alternatives. The scheme is administered by Ofgem on behalf of the Department for Energy Security and Net Zero (DESNZ).
The grants are designed to help overcome the upfront cost barrier that prevents many households from making the switch to cleaner heating technology.
Major Changes in 2024-2025
Insulation Requirements Removed (May 2024)
The most significant recent change came into effect on 8th May 2024: homeowners no longer need to install cavity wall or loft insulation to qualify for BUS grants. This change has removed a major barrier that previously prevented many households from accessing the scheme.
Previously, properties needed to have no outstanding Energy Performance Certificate (EPC) recommendations for loft and cavity wall insulation. This requirement often forced homeowners to spend an additional £2,500 on insulation upgrades before they could access heat pump grants.
We’ve already supported families by making our Boiler Upgrade Scheme one of the most generous in Europe and now we’re making heat pumps even cheaper and easier to install.
Why the Change Matters
For a typical semi-detached property, removing the mandatory insulation requirement could reduce the total cost of switching to a heat pump by approximately £2,500. This makes the transition more financially accessible and allows families to spread improvements over time rather than facing one large upfront bill.
Important note: While insulation is no longer mandatory for BUS eligibility, government guidance still strongly recommends that properties be appropriately insulated to maximise heat pump efficiency and minimise running costs.
Eligibility Requirements & Funding
Who Can Apply
To qualify for a BUS grant, you must meet all of the following criteria:
Property Ownership
- Own the property (including business properties)
- Second homes are eligible
- Rental properties you own
- Small business properties
Location & System
- Located in England or Wales only
- Replacing fossil fuel heating (gas, oil, electric, LPG)
- Valid EPC less than 10 years old
- MCS-certified installer required
Property Types Eligible
- Detached, semi-detached, terraced houses
- Flats and apartments
- Custom-built homes (self-builds)
- Some new builds with fossil fuel boilers
What’s Not Eligible
- Social housing under the Housing and Regeneration Act 2008
- Properties that have already received public funding for heat pumps or biomass boilers
- Most new-build properties (unless completed with a fossil fuel boiler)
- Properties in Scotland or Northern Ireland (separate schemes apply)
Recent Funding Increases
The government has significantly increased BUS funding in response to growing demand:
October 2024
Additional £50 million committed to meet “booming demand”
January 2025
Further £25 million added, bringing the 2024/25 total budget to £205 million
2025/26 Budget
£295 million confirmed (November 2024)
Long-term Commitment
£13.2 billion allocated to the Warm Homes Plan, which includes BUS
These funding increases demonstrate the government’s commitment to its target of 600,000 heat pump installations per year by 2028, with demand consistently outpacing initial budget allocations.
Application Process & Consumer Protection
- MCS-certified (Microgeneration Certification Scheme)
- Member of approved consumer code (RECC or HIES)
- Registered with the BUS scheme
- Proven track record of quality installations
- Property suitability assessment
- System design tailored to your home
- Quote with BUS grant already deducted
- All paperwork handled by the installer
- System installation by certified professionals
- Commissioning and testing
- Grant application submitted within 120 days
- Payment made directly to installer by Ofgem
Important Deadlines
Since May 2024, there’s a 120-day deadline for submitting applications after the heat pump is commissioned. Missing this deadline often results in grant rejection, so it’s crucial to work with organised, experienced installers.
Consumer Protection & Quality Standards
Installer Requirements
All BUS installers must hold valid MCS certification, be members of approved consumer protection schemes, and meet industry standards for installation quality.
Quality Guarantee
MCS standards ensure high-quality installations with appropriate warranties and technical support during and after installation.
Dispute Resolution
Access to dispute resolution through approved consumer codes, with single point of contact for complaints and ADR if needed.
Warranty Protection
Comprehensive warranty protection on both equipment and workmanship, with ongoing aftercare support.
Your Rights as a Consumer
Quality Standards
Guaranteed installation quality through MCS certification and industry standards compliance.
Consumer Protection
Access to approved consumer protection schemes with established complaint procedures.
Technical Support
Ongoing technical support and guidance throughout the installation process and beyond.
Warranty Coverage
Comprehensive warranties on equipment and installation workmanship with clear terms.
Dispute Resolution
Clear escalation path for complaints with access to Alternative Dispute Resolution (ADR) services.
Transparency
Right to clear, upfront pricing with BUS grant amounts clearly deducted from quotes.
Future Developments & Getting Started
📈 Application Success and Market Growth
Future Developments
Proposed Expansions (2025 Consultation)
The government is currently consulting on further BUS improvements, including:
🌬️ Air-to-Air Heat Pumps
Inclusion of air-to-air heat pumps as eligible technology under the scheme
🔋 Heat Batteries
Heat batteries as eligible technology for thermal energy storage
💳 Alternative Financing
Hire purchase and leasing options to spread costs over time
📋 Streamlined Certification
Simplified certification requirements and enhanced consumer protection
Clean Heat Market Mechanism
The Clean Heat Market Mechanism (CHMM), originally scheduled for April 2025, has been delayed to allow industry adjustment time. When implemented, it will require boiler manufacturers to also sell heat pumps, creating additional market incentives for heat pump adoption.
Maximising Your Savings
🏛️ Government Schemes
- Great British Insulation Scheme
- Energy Company Obligation (ECO)
- Local authority grants (varies by area)
- 0% VAT on heat pump installations until 2027
🏦 Mortgage Lender Cashback
- Barclays Greener Home Reward: Up to £2,000
- Halifax Green Living Award: £2,000 cashback
- Lloyds Bank Eco Home Reward: £2,000 for heat pumps
💡 Long-term Benefits
- Lower running costs compared to oil and LPG systems
- 20+ year lifespan with proper maintenance
- Increased property value in many cases
- Future-proofing as gas prices rise and electricity becomes greener
Getting Started
📋 Before Contacting Installers
- Check your EPC – ensure it’s less than 10 years old
- Identify your current heating system – what are you replacing?
- Consider your space – air source heat pumps need outdoor space
- Budget for extras – additional costs might include new radiators
🔍 Finding the Right Installer
- Verify MCS certification and BUS registration
- Check consumer code membership (RECC or HIES)
- Request multiple quotes for comparison
- Ask for local references and examples of work
Questions to Ask Installers
- Are you MCS-certified and BUS-registered?
- What’s included in your quote beyond the heat pump unit?
- How long will the installation take?
- What warranties do you provide?
- Can you handle all the BUS paperwork?
- Do you provide ongoing maintenance services?
🌍 The Bigger Picture
The Boiler Upgrade Scheme is part of the UK’s broader strategy to achieve net-zero carbon emissions by 2050. By making low-carbon heating more affordable, BUS helps reduce household emissions, improve energy security, support UK jobs, and drive innovation in the heat pump industry.
The scheme represents one of Europe’s most generous heat pump support programmes. With the removal of insulation requirements and increased funding, it’s now more accessible than ever for UK homeowners to make the switch to cleaner heating.
With grants of up to £7,500 available and no longer requiring costly insulation upgrades upfront, there’s never been a better time to explore whether a heat pump could work for your home.
This guide reflects the Boiler Upgrade Scheme rules as of August 2025. Scheme details may change – always check the latest guidance on GOV.UK or consult with an MCS-certified installer for the most current information.