EPC B today = EPC B.C.D in Autumn 2026

From autumn 2026, the methodology for dwelling Energy Performance Certificates (EPCs) will change significantly. Comparisons with existing certificates may not be possible, complicating strategies and funding plans devised to target existing ratings.

There are flaws in the current single EER methodology. It’s a simplified energy cost metric, driven strongly by the difference between grid electricity and gas costs, with homes using gas-based heating often achieving a higher rating than heat pumps. This doesn’t align with government decarbonisation objectives and is problematic where EPC ratings act as a commercial driver on projects, such as applying for grant funding, or setting standards for landlords (MEES) where C-ratings are soon to be required.

New EPCs will display the following categories:

• Fabric performance – to reflect Part L Fabric Energy Efficiency (A-G rating)
• Heating system – ranks different heating technologies based on efficiency and emissions (A-G rating)
• Smart readiness – reflects how energy systems in the home could support users to better manage their energy use (A-G rating)
• Energy cost – displayed in £/yr

As described in an earlier article, the C-rating from MEES applies to the fabric performance metric and one of the heating system or smart readiness metrics (landlords can decide). The government’s recent consultation responses suggest a C under the current methodology will be close to a C under the fabric performance category. For the heating system metric, heat pumps and low carbon heat networks should always score a C or higher, whereas gas heating, or direct electric heating with no thermal storage, won’t. A smart readiness C will reflect a combination of micro-generation (e.g. PV), smart metering, and energy storage, with details still being consulted on.

These changes were confirmed by the government, issuing a partial response to the EPC consultation ran in early 2025. A response on remaining items is expected later this year. A separate consultation on EPCs in the context of the Home Energy Model (HEM) has also just been launched, closing in March.

To aid the transition and provide continuity for existing policies and funding criteria, new EPCs will continue to show the legacy EER metric until 2029. However, new EPCs are also expected to be produced via the incoming Home Energy Model (HEM) from late 2026. It is currently unclear how homes will perform in this software vs SAP (or RdSAP), thus creating a risk that equivalence with existing EPC ratings, even when considering the same metric, will not be possible with new ones.

New EPCs will be valid for 10 years. All existing EPCs under the current methodology will remain valid for their extant life (up to 10 years). The above changes won’t apply to non-residential buildings, with the current EIR metric remaining.