Boiler Upgrade Scheme EPCs: Do You Need One in 2026?

Before May 2024, properties generally needed an EPC generated within the previous 10 years. Where loft or cavity-wall insulation appeared as a recommendation, the work normally had to be completed before voucher redemption unless an exemption applied.

From 8 May 2024, Ofgem began accepting EPCs containing insulation recommendations. A further reform then took effect on 28 April 2026, relaxing the requirement to provide a valid EPC at all. The 2026 amendment regulations came into force on that date.

For a broader explanation of the latest changes, read our Boiler Upgrade Scheme 2026 updates.

What happens if you already have a valid EPC?

If your property has a valid EPC, you do not need to ignore it or replace it simply because the rules have changed.

Ofgem’s current guidance says the installer should include the EPC reference number in the BUS application where a valid certificate exists.

An EPC remains useful because it provides information about the property’s energy efficiency and possible improvements. However, it should not be confused with the detailed heat-loss assessment needed to design a heat pump.

Your installer should assess the property itself, including its heat loss and proposed heating system, before providing the final system design and quotation. Ofgem’s guidance specifically expects a property visit and heat-loss assessment at quotation stage.

What if your EPC has expired?

An expired EPC does not automatically stop a current BUS application.

Under the current rules, you have two main options.

You can commission a new EPC before the installer applies. Alternatively, the installer can submit evidence to Ofgem without obtaining a new certificate.

An expired EPC may itself form part of that supporting evidence, but you should not assume that an old certificate alone will establish eligibility. Ofgem may require other information about the property and existing heating system.

For reference, ordinary domestic EPCs are normally valid for 10 years. You can check whether a certificate already exists using the government’s EPC service. Check whether your property has a valid EPC on GOV.UK

What evidence can replace an EPC?

Where there is no valid EPC, Ofgem’s current property-owner guidance says alternative evidence may include:

1. A utility bill dated within the previous three months.
2. The most recent available fuel receipt.
3. Photographs showing the existing heating system.
4. An expired EPC, where one is available.

Your installer is responsible for supplying the supporting evidence to Ofgem, although you may need to provide documents or photographs. Ofgem can request clarification if the information submitted is not sufficient.

This is important because the change does not mean that Ofgem has stopped checking properties. It means the scheme now allows eligibility to be evidenced in more than one way.

The application remains installer-led. See our guide to the Boiler Upgrade Scheme application process for the wider sequence.

Do you need loft or cavity-wall insulation first?

Not as a condition of BUS eligibility under the current rules.

The requirement to deal with outstanding loft and cavity-wall insulation recommendations was removed from 8 May 2024. Therefore, seeing one of these recommendations on an existing EPC does not by itself disqualify your property from BUS.

However, that should not be interpreted as meaning insulation no longer matters.

Heat pumps generally perform better when unnecessary heat loss is reduced. Ofgem recommends considering energy-efficiency improvements where they are practical and affordable. It also recommends discussing them with the installer during system design.

The key distinction is between grant eligibility and good heating design. Insulation may improve comfort, reduce heat demand or allow a smaller heating system even when it is not mandatory for the grant.

Should you still get a new EPC before installing a heat pump?

Sometimes.

If you already need an EPC for another reason, commissioning one may make sense. It can also provide a useful overview of the property’s efficiency and highlight areas worth investigating.

However, paying for a new EPC solely because you believe BUS always requires one may now be unnecessary.

Ask your installer what evidence they intend to submit before commissioning a certificate specifically for the grant.

An EPC also cannot tell you everything needed to size a heat pump correctly. A proper heat-loss calculation considers how much heat individual rooms lose under design conditions. That information helps determine heat-pump capacity and whether existing radiators can provide sufficient heat.

If you are still deciding which technology suits the property, our air source heat pump explained guide covers how a typical air-to-water system heats a UK home.

What do landlords need to know about EPCs and BUS?

The BUS rule change does not remove separate EPC obligations that apply to selling or letting property.

GOV.UK states that an EPC is generally required when a property is sold, rented out or newly built, subject to relevant exemptions. Domestic EPCs are normally valid for 10 years.

Therefore, a landlord could be in a position where BUS does not require a new EPC but property legislation requires a valid certificate for a different reason.

Treat the two issues separately:

BUS eligibility: a valid EPC is no longer automatically necessary.

Landlord or sale obligations: an EPC may still be legally required independently of the grant.

How does a BUS application work if you do not have an EPC?

The process is largely the same as any other BUS application.

First, choose an installer who is appropriately MCS certified. Ofgem confirms that the scheme is installer-led and that eligible installations must use an MCS-certified installer.

The installer assesses the property and checks the wider eligibility requirements. You then agree a quotation showing the applicable BUS grant as an upfront deduction.

If there is no valid EPC, the installer gathers the alternative evidence needed to support the application. They submit the voucher application to Ofgem on your behalf.

Ofgem then contacts you so you can confirm consent and complete identity verification. A voucher application is considered properly made once Ofgem has the information it needs, together with the required consent and identity verification.

For a step-by-step overview, see how the Boiler Upgrade Scheme works.

What BUS funding is available in September 2026?

The EPC change applies alongside the wider 2026 BUS rules.

The standard grant is currently £7,500 for eligible air-to-water and ground-source heat pumps, £2,500 for residential air-to-air heat pumps and £5,000 for eligible biomass boilers. Certain off-gas-grid properties replacing oil or LPG with an air-to-water or ground-source heat pump can receive £9,000 until 31 March 2027.

Grant values do not mean every installation qualifies. The property, previous heating system, proposed technology and installation still need to meet BUS rules.

Common Boiler Upgrade Scheme EPC mistakes to avoid

One of the biggest risks is relying on an old article, council page or installer checklist without checking when it was written.

Rules that were accurate in 2023 or early 2024 can now produce the wrong answer.

Also avoid assuming that removing the EPC requirement removes the need for evidence. Your installer still has to demonstrate that the installation meets scheme requirements.

Finally, do not treat an EPC as a substitute for heat-pump design. An EPC is useful for understanding energy efficiency, but the heating system still needs a proper property assessment and heat-loss calculation.