From 15 June 2025, landlords and letting agents across the UK will face a major change in how Energy Performance Certificates (EPCs) are calculated. The government is introducing an updated methodology known as RdSAP 10, which experts say is the most significant update in over a decade. The aim is to improve the accuracy of EPCs by requiring more detailed information about a property’s energy performance.
Under RdSAP 10, assessors must now collect additional data during site visits — including precise window measurements, insulation details, and the presence of renewable technologies such as solar panels and battery storage systems. These extra requirements mean assessments will take longer and are already leading to increased costs. Some assessors have reported price rises of £10–£30 per certificate, depending on property type.
The new system could impact how properties are rated. Flats and mid-terraced homes may see improved ratings due to more accurate heat loss calculations. However, older properties or those without documentation for past improvements — such as insulation or heating upgrades — may receive lower EPC scores. This could affect a landlord’s ability to rent out a property if it falls below the minimum required rating.
To prepare, landlords are being urged to organise documentation for any past upgrades and consider getting EPCs updated soon, especially if planning to let or sell in the near future. Although the changes may cause short-term inconvenience and cost increases, they are expected to improve the long-term reliability and value of EPC ratings across the housing market.
For more details, visit:
https://www.gov.uk/guidance/standard-assessment-procedure
Preparing for the Changes
To navigate the upcoming changes effectively, landlords and agents should.
Gather and organize documentation for all energy efficiency improvements.
Schedule EPC assessments in advance to accommodate the more detailed evaluation process.
Consult with accredited energy assessors to understand the specific implications for their properties.
By taking these proactive steps, property owners can ensure compliance with the new standards and avoid potential disruptions in renting or selling their properties.
