Ofgem published version 2.4 of its Boiler Upgrade Scheme (BUS) property owner guidance in December 2023. The update covers the scheme's grants-schemes hub and consists mainly of amendments to text to improve clarity throughout the document, plus two new paragraphs addressing digital features in the voucher application process.
The new paragraphs sit in the section on applying for the BUS voucher. Section 5.11 addresses a new digital "Cancel Application and Re-Apply" feature, and section 5.16 addresses a new digital "file upload" feature, noting the file size limit and required format for uploads1. No further detail on the file size limit or format is given in the summary of updates.
The same document records changes made in earlier versions, which remain part of the guidance. Version 2.3 added a section on grant level changes applicable from 23 October 2023, following a change notice issued by the Department for Energy Security and Net Zero, and updated the grant values and Figure 1 to reflect them1. Version 2.2 added a section clarifying the position on hybrid heat pumps1.
Other clarifications recorded across versions include:
| Area | Change |
|---|---|
| Air source heat pumps | Systems must be hydronic to be eligible (section 4.7) |
| Heating demand | The heat pump or biomass boiler must provide both space and hot water heating and meet the full demands of the property (section 4.20) |
| Commissioning | The installer is responsible for commissioning the system (section 4.22) |
| Property types | Domestic and non-domestic properties include owner-occupied homes, properties rented to tenants, second homes and holiday homes (section 4.27) |
| Park homes | Mobile properties such as park homes may be eligible if an EPC can be issued and all other requirements are met (section 4.28) |
| New builds | Properties built at scale by development companies are not eligible at the point of being built (section 4.30) |
| Self-builds | Installations in eligible self-builds do not need to supply evidence of minimum insulation (section 4.37) |
| EPCs | Properties exempt from insulation requirements still need a valid EPC at voucher application stage (section 5.13) |
| Room-in-roof insulation | Deemed distinct from loft insulation, so EPC recommendations for it do not block a voucher (section 5.23) |
On costs, section 5.15 removed a recommendation that an EPC assessment may cost £60 upwards and added text stating there is no set fee for an EPC assessment1. On consent, section 5.27 states consent is asked for only once, at the voucher application stage and not at redemption, and section 5.26 clarifies that giving consent does not confirm agreement to the installation and does not recreate any contractual arrangements between installer and property owner1.
"Section 5.11: created new paragraph to address new digital 'Cancel Application and Re-Apply' feature."
Why it matters for households
The BUS is the main grant route for households replacing a fossil fuel heating system with a heat pump or biomass boiler, so the wording of the property owner guidance determines what a home can claim and when. The clarifications on eligibility matter for homes whose circumstances sit at the edges of the scheme: park homes, second homes, self-builds and properties with EPC recommendations for room-in-roof insulation. The confirmation that a heat pump must meet the full space and hot water demand of the property, and that air source systems must be hydronic, sets the technical bar a home's system has to clear. The digital cancel and re-apply and file upload features change how an application can be corrected or evidenced once it is with Ofgem, which affects how quickly a voucher can move towards redemption. The removal of the £60 figure for EPC assessments means no set fee is stated, leaving the cost to the market.
What happens next
No further version or date is given in the summary of updates. The grant level changes applicable from 23 October 2023 are already reflected in the guidance.
Sources1 cited
- Summary of updates in the BUS property owner, ofgem.gov.uk