Some questions remain unanswered about Scottish Government plans to reform Energy Performance Certificates by late 2026, an agency expert says. 

Calum Allmond, a director at DM Hall Chartered Surveyors, says both domestic and non-domestic EPCs are included in the Scottish Government plan, a welcome change since non-domestic EPCs are often overlooked during legislative updates and methodology revisions.

The validity period for EPCs will reduce from 10 to five years, and the new digital EPC format will streamline access and provide upgrade simulations. 

Allmond says: “While these are positive steps, there are some concerns about potential confusion, delays in implementation, and unresolved impacts on existing legislation regarding sub-standard properties.”

Changes include new ratings for domestic EPCs: Heat Retention, which measures heat loss through walls, floors, and roofs; Heating System, which evaluates heating systems based on emissions, efficiency, and running costs; and a renamed Energy Cost Rating, formerly the headline rating, all of which aim to simplify EPCs by reducing jargon and offering clear guidance for improving homes.

Under the planned changes, the Heat Retention Rating will become the main headline figure on the domestic EPC, but Allmond suggests this raises questions about how this shift will affect legislation that restricts the sale or lease of sub-standard properties based on their Energy Cost Rating. If this measure is now to be less prominent, it could lead to confusion.

A proposed digital format will streamline access to the online EPC register and allow users to simulate potential improvements after upgrades, though it is possible that such simulations may include heavy disclaimers, limiting their practical reliability. Non-domestic EPCs will move to a “reference” model, aligning with the UK’s calculation methodology which compares a building’s performance to a defined reference building.

Allmond adds: “But while aligning with UK methodology is seen positively, there is inconsistency in rating scales. Scotland’s ratings will run from 0 to 100+, while the UK’s range is 0 to 150+. This discrepancy makes direct comparisons difficult and seems unnecessary. Other updates include a proposal that heating systems will be categorized as Polluting, Hybrid, Renewable, or Clean, while the Direct Emissions Rating will stay but without a banding letter and the Energy Use figure and Primary Energy Rating will still be displayed, though the exact placement remains unclear.”

He believes that the EPC Validity Period reduction ensures EPCs remain more accurate and relevant, though this still relies on triggers like property sales or leases. Expanding triggers to include significant alterations, such as insulation or heating upgrades, could improve EPC accuracy.