Energy performance certificates (EPCs) are plagued with inaccuracies and offer unhelpful advice, a study by the consumer group Which? has revealed. Calling for urgent reform, the organization urged the next government to address these issues to ensure EPCs provide homeowners with reliable and actionable information.
To investigate the accuracy of EPC assessments, Which? selected 12 homeowners across the UK and arranged for EPC evaluations between February and March. These certificates, introduced in 2007, aim to compare the energy efficiency of homes for prospective buyers and renters. The properties tested ranged from a one-bedroom flat to a five-bedroom detached house, built between 1650 and 1999.
Which? reported significant issues with the accuracy of the results and the recommendations provided. One participant did not even receive their certificate after the survey, despite having their fee refunded. Out of the 11 remaining participants, only one expressed high satisfaction with their EPC, and a mere three indicated they would recommend obtaining an EPC based on their experience. The majority, eight out of 11, reported inaccuracies, particularly regarding descriptions of key home features such as windows, roofs, and heating systems.
The report also highlighted that many participants found the suggested improvements to be prohibitively expensive.
Megan Dobney’s case was particularly striking. Her two-bedroom Victorian terraced house in London received a D rating. The EPC recommended several costly improvements, including wall insulation, floor insulation, solar water heating, and solar panels. The total estimated cost for these upgrades was up to £26,700, yet these measures would only elevate her property’s rating from D to C, saving approximately £920 annually—meaning it would take up to 29 years to recoup the investment.
“The recommended changes are extremely expensive, generally for small savings each year, and would require massive disruption,” Dobney remarked.
Rocio Concha, director of policy and advocacy at Which?, emphasized the need for reform. “Our research shows they are in desperate need of reform—current certificates are often inaccurate and only suggest costly improvements with long payback periods. The next government must make EPCs a more reliable and useful tool for householders. This should include reviewing the auditing and training requirements for domestic energy assessors and ensuring EPCs provide relevant information and clear, actionable advice for consumers,” Concha stated.
Timothy Douglas, head of policy and campaigns at Propertymark, echoed the call for improvements. He suggested the introduction of a “property passport” to enhance EPCs by maintaining a comprehensive record of a building’s energy efficiency over time. “This would enable information to be transferable across building owners and help maintain a long-term decarbonisation goal for the building,” Douglas said.
In September, Prime Minister Rishi Sunak scaled back several green targets, including requirements for landlords to upgrade homes to a minimum EPC rating of C, and delayed the ban on new petrol car sales and the phasing out of gas boilers. Despite these rollbacks, Sunak asserted that the UK remains on track to meet its 2050 net-zero commitments.
As the nation grapples with the challenge of improving energy efficiency, the findings from Which? underscore the need for accurate, actionable, and affordable guidance for homeowners to make meaningful improvements.