As of 1 February 2023 the approved methodology for producing EPCs for existing non-domestic buildings in Wales will be the National Calculation Methodology (NCM) for buildings other than dwellings in England, 2021 version.
Changes to the non-domestic EPC methodology in Wales
We would like to inform you that as of 1 February 2023 the approved methodology for producing EPCs for existing non-domestic buildings in Wales will be the National Calculation Methodology (NCM) for buildings other than dwellings in England, 2021 version.
This is an interim step ahead of the adoption of the NCM for buildings other than dwellings in Wales, 2022 version on 29 March 2023, when the new building regulations for non-domestic buildings in Wales are introduced.
We are expecting approved EPC software packages to implement the changes on time for these changes.
You can download the Commercial EPC Conventions Issue 8 from the CIBSE Certification website.