NIBE Installers Guide
BEIS BUS (Boiler Upgrade Scheme)

Everything Installers need to know about the boiler upgrade scheme (BUS)

There will be no extension to the RHI beyond midnight 31st March 2022. Applications must have been submitted by this point with no exceptions.  

  • Please note that NIBE cannot guarantee that heat pumps will be installed in time for the RHI deadline on 31st March 2022 and cannot be held responsible for possible delays in the delivery and installation process.
  • If you think an install is going to finish after this date, then you should communicate to the customer that they will not be able to get RHI funding and should explore the BUS funding instead.
  • There is no clear start date for the BUS yet, but it is expected to start 1st April 2022. Applications for vouchers will close after 31st December 2024.

The Statutory Instruments for the BUS have now been published and can be read here: Draft: Boiler Upgrade Scheme (England and Wales) Regulations 2022 (

The below note summarises our current understanding of the Boiler Upgrade Scheme as of December 2021.

DRHI closure and amendments

Changes were made to the DRHI by BEIS in light of its 2022 deadline of midnight 31st March. No extensions to the scheme will be made (even if units are delayed and/or unavailable) and to secure RHI funding installs need to be commissioned and final application for RHI funding made before midnight 31st March 2022. There are also some small amendments that will be made once the scheme has closed to best monitor the scheme until payments finish, including amendments to the regulation for replacement of parts of plants and annual declarations, altering metering requirements (occupancy/183 day rule) and simplifying Metering and Monitoring Service Package arrangements; ensuring biomass fuel quality standards through the BSL scheme, and allowing DRHI payments to be backdated to change of ownership date of a property.

What is the Boiler Upgrade Scheme (BUS)?

The Boiler Upgrade Scheme is a newly announced £450 million scheme that will offer capital grants to households and small businesses looking to install heat pumps and, in some limited cases, biomass boilers. The BUS is expected to start in April 2022. The scheme is expected to help install 90,000 heat pumps over three years.

Under the scheme, homeowners will be able to claim grants towards the installation and capital costs of up to £5,000 of ASHPs and biomass boilers, and £6,000 for GSHPs. The heat pump must provide heat solely to a single property and for the purpose of meeting the full space and hot water heating demand.

BUS vouchers will have validity periods of 3 months for air source and 6 months for ground source heat pumps - the voucher process will be installer-led

Customer Journey and Application Process

The BUS application process for grant funding will be installer-led. See diagram below from BEIS for a current example of the user’s journey, please note this is subject to change.

Customer Journey & Application Process


The BUS comprises a two-stage voucher application process - the first stage will require basic information like installation postcode, technology type and customer contact details. Once the voucher is issued and installation completed, the second stage of voucher redemption and subsequent grant allocation is completed upon submission of the MCS certificate. Therefore, all installers applying to the scheme must be MCS certified and members of a Consumer Code to ensure customers are protected by a Trading Standards Institute Approved Code of Practice. Further procedural guidance for installers will be published before the start of the scheme (we will share this with you when it is available).

Information required for the grant application:

  • The installer’s name, any trading or other name by which the installer is commonly known, and registered office (where applicable) or principal place of activity, and company registration number (where applicable),
  • The installer’s membership number in relation to the Microgeneration Certification Scheme, or an equivalent scheme, under which they are certified,
  • The name of the consumer code of which the installer is a member, and their membership number in relation to that consumer code,
  • Where the grant application is made on behalf of the installer by an individual, information to enable the Authority to satisfy itself— (i) as to the identity of that individual, and (ii) that the individual has authority from the installer to make the grant application,
  • Details of a bank account in the installer’s name which accepts pound sterling deposits in the United Kingdom,
  • Details of the property, including:
  • The address,
  • Whether it is a dwelling or a non-domestic property,
  • Whether it was, or will be, first occupied as a dwelling or first used as a non-domestic property, (as applicable) before the date on which the eligible plant was, or is to be, commissioned,
  • In the case of a grant application relating to the installation of a biomass boiler, whether it is in an urban area or fuelled by mains gas.
  • details of the original heating system in relation to the property (where applicable),
  • details of the eligible plant to be installed in the property, including whether it is an air source heat pump, a ground source heat pump, or a biomass boiler,
  • where the property falls within regulation 5(1)(c) (property first occupied or used before the date on which the plant is commissioned), the unique reference number for the valid energy performance certificate for the property,
  • details of the quote provided by the installer to the owner of the property for the installation of the eligible plant,
  • the name, address, email address, and telephone number of the owner of the property, and
  • such other information, or declarations from the installer, as the Authority may require.

If the information submitted for a voucher application is deemed not sufficient then additional information will be requested with a 14 day window for the installer to provide. Any voucher applications that are denied must be notified within 14 days of that decision being taken with the reasoning for the decision being explained to the installer. Installers must hold on to the information used for making the grant application for 6 years after the voucher redemption.

To redeem a voucher the following information will be needed:

  • Unique reference number from MCS
  • Unique identifier of the voucher
  • Name of the manufacturer, model and serial number of the eligible plant installed
  • Biomass emissions certificate (for biomass installs only)
  • Further planning evidence for properties that are Listed or in a Conservation area etc

The scheme administrator could undertake property inspections to check that the installation carried out meets the requirements of the scheme with no less than 2 days’ notice for the property owner.


The scheme will be open to:

  • All homeowners, small landlords and private landlords in England and Wales.
  • It will not be made available to social housing properties or new builds (apart from self-build).
  • Generally, anyone replacing an existing fossil fuel heating system or direct electric system.

Applications can be made for Air Source Heat Pumps[1] for up to £5,000 (note that PVT is expected to be eligible under the ASHP definition) and for Ground Source Heat Pumps[2] for up to £6,000. The scheme will support systems up to a capacity limit of 45 kWth.

A property is eligible for the grant only if the EPC does not have a recommendation for loft and/or cavity wall insulation to be installed, unless the property is a Listed Building, in a Conservation Area or it is not feasible due to the property structure. However, the property owner can also instruct the installers to carry out the installation anyway without loft or cavity wall insulation and the property owner intends to install these measures at a later date and obtain a new EPC before the date on which the application to redeem the voucher is made.

BUS eligibility is prohibited for properties that, a) have previously received RHI, Green Homes Grant, Home Upgrade Grant, or any other government funding, or b) have installations with a commissioning date prior to the 1st of April 2022 BUS launch date.

Budgets and voucher allocation

The total budget allocation will be confirmed by 1st April 2022. The total value of the vouchers issued will be published each quarter by BEIS.