Great British Insulation Scheme

How installers and the supply chain can get involved with the Great British Insulation Scheme.

The Great British Insulation Scheme is a government energy-efficiency scheme that is administered by Ofgem. It is designed to deliver improvements to the least energy-efficient homes in Great Britain to help tackle fuel poverty and reduce carbon emissions. To find out more about the Great British Insulation Scheme, see the About the scheme web page.

The scheme will deliver the rapid installation of value-for-money insulation measures and, in some cases, heating controls to support people living in the least energy-efficient homes. You can find more details about the scheme here.

If you are an installer and interested in delivering measures, you need to contact an obligated supplier. To be eligible to deliver measures under the scheme, all installers must be a TrustMark-registered business.

To access all guidance and relevant forms, please see our Contacts, guidance, and resources web page.

What measures can be installed?

While the Great British Insulation Scheme has been designed to complement the Energy Company Obligation (ECO4) scheme, unlike ECO4’s whole house approach, this scheme will mostly deliver one insulation measure to each household to reach more homes. It will reduce energy bills for those people on the lowest incomes which the scheme refers to as the low-income group, as well as those with lower Council Tax band homes, called the general group.

Both groups will be eligible for the following insulation measures:

  • cavity wall (inc. party wall)
  • loft
  • solid wall
  • pitched roof
  • flat roof
  • under-floor
  • solid floor
  • park home
  • room-in-roof

Where an eligible insulation measure is installed in owner-occupied premises in the low-income group, certain heating controls, such as room thermostats, would also be allowed, as a ‘secondary measure’.

Higher-cost measures - such as solid wall insulation - would be more likely to require a contribution from the household.



Evidencing measures

The Great British Insulation Scheme and ECO4 forms are used to collect and provide evidence of measure eligibility, all forms can be found on the Energy Company Obligation Forms and Tables page.

What delivery standards are required?

All measures available under the scheme must be delivered according to PAS2030/2035 (Publicly Available Specification) standards, with which tradespeople using the government-endorsed quality scheme are required to comply when carrying out domestic retrofit work.

Unlike ECO4, there is no minimum requirement under the Great British Insulation Scheme for a property’s Standard Assessment Procedure (SAP) rating to be increased through the measure.

Are there opportunities for innovation?

The Great British Insulation Scheme offers incentives designed to support the delivery of innovative measures that can provide further energy efficiency improvements, or that offer additional benefits. Only obligated suppliers can apply under the innovation routes.

If you have a new, or innovative, product or system that you wish to have supported under the scheme, you need to work with an obligated supplier who will liaise with Ofgem and submit the application to us.

More information on innovation is outlined in the Great British Insulation Scheme Guidance: New Measures and Products.

Further details, including application forms for the innovation routes, are available on the Great British Insulation Scheme Innovation web page.

Are there appropriate guarantees for the Great British Insulation Scheme?

Ofgem does not administer appropriate guarantees or financial protection for measures installed on the Great British Insulation Scheme. The current list of appropriate guarantees can be found on the TrustMark website and any queries regarding these should be directed to TrustMark.

How does Ofgem engage with stakeholders?

We believe that engaging with stakeholders when designing and delivering schemes brings real benefits. We do this via forums and working groups which gather contributions from a range of stakeholders about the main operational and delivery issues in the Great British Insulation Scheme.

To find out more, see the section dedicated to stakeholder engagement.

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