Over 30,000 homes in the UK have been fitted with faulty insulation through government schemes, potentially exposing residents to damp and mould, ministers have disclosed.
For the first time, the government has officially disclosed the number of homes affected by poor-quality insulation work carried out under the ECO4 and Great British Insulation Scheme since their launch in 2022. More than 30,000 properties have reportedly suffered from issues related to sub-standard installations, with ministers describing the situation as a “systemic failure.”
Energy Consumer Minister Miatta Fahnbulleh told Parliament that while some affected homes have received corrective work, any residents with ongoing concerns are encouraged to contact Ofgem.
Among those affected is a man from Luton, identified only as Mohammed, who told the BBC he has been unable to sleep in his bedroom due to severe damp and black mould. In 2023, he applied for external wall insulation under the ECO4 scheme, hoping it would make his home warmer and more suitable for his elderly father, who had chronic asthma.
However, instead of improving conditions, Mohammed says the poorly installed insulation caused extensive damp and mould, particularly in his father’s bedroom. He believes the exposure to mould contributed significantly to his father’s declining health.
“Day after day, he was breathing that in, and it just made his lungs worse. Eventually, it was too late,” he said.
Mohammed has spent the last two years trying to get the installer to take responsibility for the damage. “It’s been mentally exhausting,” he added, noting that he now lives with black mould, damp, and crumbling plaster in his own bedroom.
Following a BBC investigation last year that exposed links between faulty insulation work and the rise of damp and mould in homes, the government commissioned an audit of 60,000 properties that had received insulation under the ECO4 and Great British Insulation Scheme (GBIS).
In a written statement to Parliament in July, Energy Consumer Minister Miatta Fahnbulleh shared early audit results, revealing that over 30,000 homes were found to have insulation installed below acceptable standards—conditions that could contribute to the development of damp and mould.
The government has stated it is “working at speed” to identify and fix substandard insulation installations, assuring that homeowners will not bear the cost of remediation.
Ministers also pledged to unveil new plans aimed at reforming the consumer protection framework, with the goal of “restoring trust and helping more people reduce their energy bills.”
However, the scale of the challenge is significant, as tens of thousands of homes are expected to require repair work. Mohammed, whose home has been affected, is currently in discussions with his installer and TrustMark—the regulatory body overseeing insulation standards—to resolve the issues.
In the meantime, he remains deeply concerned about the impact on his family’s health.
“We’re breathing in poor air due to the damp, mould, and dust,” he said.
Since 2010, government schemes have delivered solid or external wall insulation to over 260,000 properties across the UK.
At present, audits are being conducted only on homes insulated from 2022 onwards. Ministers argue that earlier schemes are not being reviewed because “current data suggests there is not a widespread issue” in those installations.
BBC News, September 2025
