Lauren James, Graduate Surveyor at StephensonsRural, explains what the biggest Energy Performance Certificate (EPC) update in over a decade means in practice, and why landlords in particular should take note.

Energy Performance Certificates (EPCs) are now being assessed using a new, more detailed methodology, the most significant change to the system in over 10 years.

Known as RdSAP 10 (Reduced Data Standard Assessment Procedure), the updated approach improves the accuracy of EPC ratings by requiring assessors to collect more specific data about a property. The previous methodology used assumptions regarding how buildings are constructed and occupied.

EPC assessors will now  record and collect more data, including the type of glazing, heating system efficiency and home improvements such as insulation, but this is only reflected if there is evidence.

One of the key improvements is how heating systems are assessed. Under the previous system, energy efficiency was often underestimated due to limited verification. The new methodology introduces a hierarchy that prioritises real documentation, meaning landlords who have invested in upgrades like new boilers or renewable heating systems can now have those reflected in the EPC, as long as records are available.

The new standards came into effect on 15 June 2025.

What the EPC updates mean for landlords and tenants

For landlords, this means being more proactive, not only in maintaining energy performance but in documenting it. EPCs remain a legal requirement when letting property, and while the current minimum standard is an E, the government has proposed raising this to a C by 2030. An accurate EPC can influence both rental value and future compliance.

For tenants, the changes offer greater transparency. With more accurate data, EPCs can better reflect a property’s true energy efficiency, helping renters make more informed choices and potentially reduce energy bills in the long term.

If you're a landlord preparing to let a property, or you’re considering energy improvements, StephensonsRural can help you understand the new EPC standards.  Get in touch with the team for advice and support.