It can appear a daunting prospect to replace a heating system with one that’s low-carbon. But the UK boiler upgrade scheme makes it easier—and less expensive—than you might think. Whether landlord or homeowner, follow this step-by-step guide for an easy route through application, what’s to come next, and making best use of government incentives.
What Is the Boiler Upgrade Scheme?
The boiler replacement scheme (BUS) is a UK government program to pay residents for installing new low-carbon heating systems in place of old conventional gas boilers. It is one of the programs under the broad net-zero emissions campaign and seeks to offer sustainable heating at a reasonable cost.
Under this scheme, eligible properties within England and Wales can be furnished with up to:
- You can get up to £7,500 off the cost of installing an air source heat pump through the scheme.
- £7,500 for a ground source heat pump
- Homeowners in rural areas may be eligible for up to £5,000 towards a biomass boiler installation under the scheme.
This isn’t a loan—it’s a grant. The grant doesn’t need to be repaid—it’s a direct contribution toward your upgrade.
Who Is Eligible?
Before applying, make sure you tick the right boxes:
- You own the property (home or small commercial building)
- The building has a valid Energy Performance Certificate (EPC)
- Your property must not have any unresolved recommendations for loft or cavity wall insulation on its EPC.
Note: This is where government grants for loft insulation come in. If your EPC recommends insulation upgrades, you’ll need to sort that out first. Luckily, separate grants often cover these costs too.
How to Apply for the Boiler Upgrade Scheme: A Step-by-Step Guide
Step 1: Choose an MCS-Certified Installer
You can’t apply directly. Instead, your installer applies on your behalf. The first thing you’ll need to do is select an installer certified by the Microgeneration Certification Scheme (MCS). These professionals are approved to install low-carbon heating systems and handle the BUS application.
Where to find one:
You can use the MCS installer search tool to find certified professionals near you.
Step 2: Get a Quote
Your chosen installer will visit your property, assess what’s needed, and give you a quote. This quote includes the grant discount upfront—so you’ll see the savings straight away.
Step 3: The Installer Applies
Once you agree to the quote, the installer will apply to Ofgem (the scheme administrator) for the voucher. At this stage, there’s nothing you need to do—simply wait for the confirmation.
Voucher timelines:
- Vouchers are valid for three months for air source and biomass systems.
- 6 months for ground source heat pumps
Step 4: Installation
After the voucher is approved, your installer will carry out the work. You’ll only pay the amount left after the grant is deducted.
Step 5: Completion & Confirmation
Once the system is installed, your installer will notify Ofgem, submit the necessary documents, and redeem the voucher. That’s it—you’re officially upgraded!
Real-Life Example: The Jones Family in Essex
The Jones family lived in a semi-detached house with an aging gas boiler. After an EPC review recommended better insulation, they used government grants for loft insulation to upgrade their roof. Then, they applied for the boiler upgrade scheme via a certified installer.
They opted for an air source heat pump with a total cost of £11,000. Thanks to the £7,500 grant, they only paid £3,500—significantly less than expected. In just a year, they reported 30% lower energy bills and a more consistent indoor temperature, even during winter.
Benefits of the Boiler Upgrade Scheme
- Lower energy bills: Heat pumps are up to 4x more efficient than gas boilers.
- Reduce carbon footprint: Switching to low-carbon systems helps tackle climate change.
- Government-backed funding: No repayments, just upfront savings.
- Increase property value: Homes with energy-efficient features are highly sought after by buyers.
What About Loft Insulation?
As mentioned earlier, one of the eligibility conditions is a proper insulation setup. If your EPC recommends adding loft insulation, it must be completed before BUS installation.
Pro tip: Look into government grants for loft insulation first. These often cover up to 100% of the cost and can be applied for through schemes like:
- ECO4 (Energy Company Obligation)
- Local Authority Delivery (LAD)
Check with your council or energy supplier for available grants in your area.
Common Mistakes to Avoid
- Not checking the EPC: Ensure no outstanding insulation recommendations.
- Avoid hiring non-certified installers: Only MCS-approved professionals are authorized to handle your application.
- Missing deadlines: Voucher expiry means you’ll need to reapply from scratch.
Case Study: Small B&B in Wales
Sarah runs a five-room B&B near Brecon Beacons. Her oil boiler was unreliable and expensive. After checking eligibility, she used the boiler upgrade scheme to install a ground source heat pump.
With a grant of £7,500, she invested the rest into improving her B&B’s thermal performance. Guests now enjoy warmer rooms and Sarah’s heating costs have dropped by nearly 40%.
Her online reviews even improved—guests appreciated the eco-friendly heating system.
Final Thoughts
Applying for the boiler upgrade scheme doesn’t have to be complicated. With the right installer and a clear understanding of the process, you can reduce your energy bills, improve comfort, and make your home future-ready.
Plus, by combining the BUS with government grants for loft insulation, you’re setting your home up for maximum energy efficiency—and long-term savings.
