Major Changes to Energy Performance Certificates Coming This Month

The Energy Performance Certificate system is about to experience its most significant transformation in over a decade, with major changes taking effect on 15 June 2025. These updates will fundamentally alter how properties are assessed for energy efficiency, bringing particular implications for homeowners, landlords, and prospective buyers throughout our local area.

The cornerstone of these changes lies in what's known as the Reduced Data Standard Assessment Procedure, or RdSAP. This methodology has underpinned domestic energy assessments for existing homes for years, using assumptions about building construction and occupancy patterns to generate energy efficiency ratings. The new version, RdSAP 10, represents a comprehensive overhaul designed to bring Energy Performance Certificates much closer to reality.

The transformation addresses long-standing concerns about EPC accuracy, particularly for certain property types that have historically been disadvantaged by the previous system's default assumptions. For residents in Rugby and the surrounding villages, this could mean significantly different ratings for their homes, especially those living in flats and mid-terrace properties.

More Detailed Property Assessments

Under the new system, energy assessors will collect far more specific information about each property they evaluate. This includes detailed recording of glazing types and their condition, precise heating system efficiency based on actual evidence such as model numbers or manufacturer data, and the presence of modern features like smart heating controls.

Perhaps most crucially, home improvements such as added insulation or new windows will only be reflected in the EPC rating if proper evidence can be provided. This represents a fundamental shift from the previous approach, where assessors could make reasonable assumptions about improvements that appeared to have been made.

The change means that EPCs will now depend much more heavily on the documentation that property owners can provide. For those considering selling or letting properties in Warwickshire, this documentation requirement could prove critical to achieving an accurate and favourable energy rating.

One of the most significant changes concerns how heating systems are evaluated. Previously, when a heating system's details couldn't be verified, the assessment would rely on default assumptions that often underestimated the system's efficiency. The new methodology introduces a hierarchy that prioritises actual evidence over these assumptions.

This change could work in favour of many property owners who have invested in efficient heating systems but may not have kept adequate records. However, it also means that if no documentation can be provided, the system's efficiency may be rated lower than before, potentially impacting the overall EPC score. For homeowners in our town who have made heating upgrades over the years, gathering supporting documentation now could prove invaluable.

The updated system addresses a long-standing issue that has affected many residents in the local area. RdSAP 10 adjusts how heat loss is calculated for flats and terraced homes, which were previously disadvantaged by default assumptions that didn't accurately reflect their energy performance.

This refinement in methodology includes improved methods for calculating floor area and insulation levels, providing a more precise understanding of a home's heat retention and energy use. For owners of these property types, the changes could lead to improved EPC ratings that better reflect their homes' actual energy efficiency.

Implications for Property Transactions

The timing of these changes creates important considerations for anyone involved in property transactions. Landlords will need to become more proactive in maintaining and providing evidence of energy improvements, as EPCs remain a regulatory requirement for letting properties. The current minimum standards mean that an inaccurate or unexpectedly low rating could potentially block a tenancy.

For those selling properties, accurate records and receipts will become critical, particularly for improvements such as insulation upgrades, heating system replacements, and double glazing installations. EPC ratings might initially appear to drop if no evidence is provided, even when significant improvements have been made. Having a clear paper trail can protect property owners from unnecessary retrofit costs and help them achieve the rating their property deserves.

Property professionals are strongly advising owners to begin gathering relevant documentation immediately. This includes receipts for any energy efficiency improvements, warranties for heating systems, certificates for insulation work, and records of window replacements or upgrades.

The changes also mean that prospective buyers can have greater confidence in the accuracy of EPCs they encounter. Those looking to purchase homes may find they can use this information more effectively to identify genuinely energy-efficient properties, potentially helping them secure homes with lower ongoing energy costs.

Whilst these changes represent the most comprehensive update to the EPC system in over a decade, they form part of ongoing efforts to improve the accuracy and usefulness of energy performance assessments. The property industry has welcomed improvements that make EPCs more robust and meaningful, though there are ongoing calls for clearer guidance and realistic implementation timelines to help the sector adapt.

For homeowners and landlords throughout the region, the message is clear: preparation is key. Those who take time now to gather evidence of their properties' energy efficiency improvements will be best positioned to benefit from the new, more accurate assessment system when it takes effect this month.