Yes. And the rule change in May 2024 has just made this ridiculously easier. You can apply for the full £7,500 grant under the Boiler Upgrade Scheme without needing to insulate the loft or cavity walls first.
The necessary upgrade requirement? Gone! I still have to have a valid EPC, but that’s it!
This is important, I think, because it means that with old systems, homeowners had to spend 1,000 to 3,000 pounds on things like insulation before touching any grant money. But with new systems, I can just get a heat pump and think about that later—maybe not even bother if I’ve got a good house.
What Changed With EPC Requirements?
The Boiler Upgrade Scheme in Wales used to gatekeep grants behind insulation upgrades. If your EPC flagged unresolved loft or cavity wall recommendations, no grant. You’d pay £2,000+ for insulation before BUS considered your application.
The May 2024 Rule Shift
The government scrapped mandatory upgrades in May 2024. Now, any valid EPC—rated A through G, under 10 years old, qualifies you.
No forced insulation. No checklist. Just prove your property was assessed.
This exploded uptake. Solid walls, listed buildings, already-insulated homes flagged for minor tweaks—all suddenly eligible.
What You Still Need
Check your EPC free at gov.uk. You need the lodgement number confirming it’s registered.
EPCs last 10 years. Expired or never had one? Book a surveyor (£50-£100). Takes an hour.
Don’t confuse “no upgrades required” with “no EPC needed.” The certificate proves baseline efficiency. BUS just doesn’t force improvements anymore.
How Do Different Grant Schemes Handle Upgrades?
Not all heat pump grants work the same way. Here’s which schemes push insulation and which don’t.
Boiler Upgrade Scheme (BUS)
BUS provides £7,500 for air/ground source heat pumps replacing fossil fuels or old electric heating. Zero insulation requirements since May 2024.
Your installer uploads your EPC, Ofgem approves, and the grant is deducted upfront. Runs through 2028 minimum. Add 0% VAT until March 2027, and you save £9,000+ on £10,000-£20,000 installations.
Covers owner-occupied homes, rentals, and self-builds. Excludes new builds and social housing.
ECO4 for Low-Income Households
ECO4 targets EPC E-G homes and benefits recipients (Universal Credit, Pension Credit). Still bundles insulation with heat pumps—but it’s fully funded.
Zero cost if you qualify. ECO4 installs both heat pumps and insulation where needed. Upgrades aren’t mandatory for eligibility, but are often included for free.
Low-income with D-G rating? ECO4 beats BUS.
GBIS and Local FLEX Schemes
The Great British Insulation Scheme focuses on insulation but pairs with BUS. You can take one without the other.
Local FLEX schemes (council-run) fund heat pumps after EPC checks. No mandated upgrades, though encouraged. Varies by region.
Scotland and Wales Programs
Scotland’s Warmer Homes scheme and Wales’s equivalents offer free heat pumps to qualifying households without upgrade requirements. Income-based eligibility applies.
Different rules than England’s BUS, but same principle: EPC needed, upgrades optional.
Why Would You Skip Insulation Upgrades?
Insulation improves efficiency, so why skip it?
Your Home Is Already Decent
EPC C or higher? Your insulation is probably fine. Heat pumps work efficiently without touching them. Even D-rated properties with solid walls or newer double glazing don’t desperately need upgrades.
Phased Retrofitting Makes Sense
Want the heat pump now, insulation later? Fair approach. Install the heat pump, lock in £7,500 grant and 0% VAT, then tackle insulation with separate GBIS or ECO4 funding. Phasing spreads costs and disruption.
Insulation Isn’t Possible
Listed buildings face planning restrictions. Solid walls need expensive external insulation (£8,000-£15,000). Hard-to-treat properties can’t be upgraded easily. The old rules blocked these homes entirely.
Speed Over Perfection
BUS applications with insulation projects take months. Heat pump-only installs? Days to approve, 1-2 days to install. Broken boiler? Skipping upgrades accelerates everything.
The Trade-Off
Skipping insulation costs 10-20% more in running costs. Well-insulated home: £800/year. Poor insulation: £950-£1,000.
Still cheaper than oil (£2,000+) or gas (£1,200+). Payback stretches from 5-7 years to 6-9 years. Still profitable long-term.
Who Qualifies for Grants Without Upgrades?
Let’s get specific about eligibility, because not everyone qualifies even without the insulation barrier.
| Criteria | Requirement |
| Ownership | Private owner or landlord (tenant consent for ECO4 rentals) |
| Current Heating | Fossil fuel (oil, gas, LPG, coal) or electric resistance systems |
| EPC Status | Valid certificate under 10 years old, any rating A-G |
| Location | England or Wales (Scotland/NI have separate schemes) |
| Installer | MCS-certified professionals only |
Benefits recipients (Universal Credit, Pension Credit, etc.) get ECO4 priority with potential full funding. Everyone else uses the BUS.
Social housing tenants don’t qualify for BUS—landlords handle upgrades separately. New builds under construction are excluded (no prior heating to replace).
How Do You Actually Apply?
The application process is simpler without insulation complications.
Step 1: Pull your EPC from gov.uk. No EPC or expired? Book a Domestic Energy Assessor (£50-£100). Assessment takes under an hour.
Step 2: Get quotes from 3 MCS-certified installers (find via ofgem.gov.uk). Prices vary £2,000-£5,000 for identical systems. Your installer handles the entire BUS application.
Step 3: Installer visits, checks outdoor space, electrical capacity (7-11kW needed), and radiator compatibility. Produces a quote showing full cost minus £7,500 grant.
Step 4: Installer submits to Ofgem. Approval in days. Grant pays directly to the installer, deducted upfront. Installation takes 1-2 days. Commissioning completes within 120 days.
ECO4 Alternative: On benefits? Use eligibility checkers (eco4.co.uk) before contacting installers. Might cover everything for free.
What Are the Real Savings?
Upfront Cost Reduction
- Heat pumps cost £10,000-£20,000 installed.
- BUS grant: -£7,500
- 0% VAT saving: -£1,500
- Net cost: £1,000-£11,000 (typically £3,000-£8,000 for ASHP)
Skip forced insulation, avoid another £1,000-£3,000 in spending.
Annual Running Costs
- Oil heating: £2,000+/year
- Gas heating: £1,200-£1,500/year
- Heat pump (no upgrades): £900-£1,100/year
- Heat pump (with insulation): £700-£900/year
You save £800-£1,100 annually versus oil, £300-£600 versus gas. Insulation adds £100-£200 more, but the bulk comes from the heat pump.
Payback
- Without upgrades: 6-9 years
- With upgrades: 5-7 years
Both work. Heat pumps last 20+ years—profitable either way for 11-15 years.
When Should You Actually Upgrade Insulation?
Skipping works for many homes, but not all.
EPC E-G Ratings: Insulation dramatically improves performance. You’ll spend 20-30% more annually without it. GBIS and ECO4 fund insulation post-BUS. Two-stage approach: heat pump now, insulation in 6-12 months.
Hard-to-Heat Rooms: Cold spots or drafty areas waste heat. Voluntary GBIS upgrades cost nothing if you qualify.
Long-Term Goals: Staying 15+ years? Insulation pays for itself. Cumulative savings compound over decades. Heat pumps work fine without it, but optimal performance needs insulation.
Final Thoughts
Check your EPC today at gov.uk. Quote 3 MCS installers. Low-income? Try ECO4 first for fully funded installs.
BUS grants run through 2028 minimum, but the 0% VAT ends March 2027—that’s £1,500 disappearing if you delay. Installers book months ahead as deadlines approach.
You don’t need perfect insulation to save money. You need a heat pump and a valid EPC. The rest is optimisation, not obligation
