Installers who are deemed responsible will be forced to fix the problems out of their own pockets.
The government has taken immediate action after routine checks found widespread cases of poor-quality solid wall insulation installed Energy Company Obligation 4 (ECO4) and Great British Insulation Scheme (GBIS).
It said that poor-quality installations were the result of years of a failed system, with ministers now committed to introducing new reforms to drive-up quality and protect consumers through the Warm Homes Plan.
Routine checks carried out by TrustMark, the independent body which oversees tradespeople working in homes, have uncovered examples of substandard solid wall insulation fitted since 2022 under ECO4 and GBIS.
As soon as these issues were identified, the government said it took immediate action to ensure installers were swiftly suspended, expanded checks of solid wall insulation measures installed under both schemes, and implemented a comprehensive plan to begin an immediate repair process.
The government also said it had instructed the energy regulator, Ofgem, to take oversight of this work to ensure it is swiftly delivered.
Ofgem has now begun writing to all the households affected, explaining that qualified professionals have started a system of checking every installation under these schemes.
In some cases, an on-site visit will then follow to determine whether any insulation work carried out requires a repair.
If it does, the certification body that oversees the installer, or TrustMark, will arrange to fix the problem as soon as possible.
The government said it was confident that the ‘systemic issues’ were particular to solid wall insulation installed under ECO4 and GBIS. This is because there is a stronger system of checks and balances in place for other energy efficiency schemes delivered through local authorities and social housing providers.
Minister for Energy Consumers Miatta Fahnbulleh said: “I know this news will be concerning for people who have had external or internal wall insulation fitted through either scheme we have inherited.
“That is why we are taking action to put this right, forcing installers to fix any poor-quality installations as soon as possible and at their own expense.
“Affected households should look out for a letter from Ofgem, which will set out steps to resolve any issues.
“It is clear the existing system of protections for consumers we inherited is in dire need of reform. This will be front and centre of our Warm Homes Plan, as we work to make sure no households are let down in this way again.”