Energy Saving Trust responds to EPC reform consultation

The Energy Saving Trust published its response to the Department for Energy Security and Net Zero consultation on reforms to the Energy Performance of Buildings Regime on 7 October 2025¹. The charity set out positions on each of the metrics proposed for EPCs, the certificates that grade a home's energy performance¹.

On cost, the Trust said it strongly agrees that an energy cost metric should appear on certificates, and that a figure in pounds per square metre per year should be the primary metric, with the modelled running cost for the property as a secondary metric¹. It argued that a rating is only useful for comparison if the difference in cost terms is known, giving the example of two properties with the same £/m2/yr rating where one is larger than the other¹. It also strongly agreed that a fabric performance metric should be displayed, and recommended that heat loss coefficient and heat loss parameter are recorded in the publicly accessible online database as a minimum¹.

The Trust strongly agreed with a heating system metric, provided it is based on the carbon efficiency of the system, and suggested greenhouse gas emissions per unit of heat delivered, in kg CO2e per kWh, as a simple measure¹. It said design efficiency (SCoP) is not a useful indicator of likely in situ performance (SPF) and should not be used as a basis for a metric, citing the Electrification of Heat report and analysis of Renewable Heat Incentive metered installations¹. It suggested that heat pump efficiency in the metric initially be based on technology type and either design flow temperature or the unit's maximum flow temperature¹. It agreed with a smart readiness metric, citing Cornwall Insight's estimate that household flexibility could deliver an annual saving of £14.1 billion for Great Britain consumers and the energy system in 2040¹.

The Trust strongly disagreed with displaying an energy use metric, calling it less relevant to the occupant and potentially confusing, and said that if one were used it should be delivered energy¹. It disagreed with a separate carbon metric, on the basis that a carbon-focused heating metric already covers the main area where emissions can be reduced¹.

"This is our response to the Department of Energy Security and Net Zero's consultation on 'Reforms to the Energy Performance of Buildings Regime'."

Why it matters for households

An EPC is the document a householder meets when buying, selling or renting a home, and the metrics chosen decide what it actually tells them. The Trust's preference for a cost figure per square metre, alongside the property's modelled running cost, is aimed at making two homes genuinely comparable on bills rather than on a letter grade alone¹. Its support for a fabric metric rests on thermal comfort and lower energy demand, which it links to permanently lower bills and reduced dependence on volatile fossil fuel markets¹. A carbon-based heating metric would shift the emphasis onto the fuel and technology in the home, which is where most household carbon emissions arise¹. The Trust also wants certificates to point households to schemes they may be eligible for, such as the Energy Company Obligation, the Great British Insulation Scheme and the Boiler Upgrade Scheme, and to impartial advice, and it repeated its call for a national advice service for England¹. Its response covers England and Wales¹; separate arrangements apply under energy and buildings policy in Scotland and energy and buildings policy in Wales.

What happens next

The response was published on 7 October 2025¹. The consultation was run by DESNZ, the department responsible for the regime¹. No date for the government's response to the consultation, or for any resulting changes to EPC regulations, has been reported¹.

Sources1 cited

1. Energy performance of buildings regime: response - Energy Saving Trust, energysavingtrust.org.uk