The UK Government announced on 23 January 2025 the action it is taking in response to poor quality workmanship by companies installing solid wall insulation1. The measures include suspending installers and protecting consumers, according to a written statement from Jayne Bryant, the Welsh Government's Cabinet Secretary for Housing and Local Government1.
The announcement relates to two programmes inherited by the new UK Government: the Energy Company Obligation 4 (ECO4) scheme and the Great British Insulation Scheme (GBIS), which operate across Great Britain1. The Cabinet Secretary said she had received assurances from the UK Government that any works to correct deficiencies will be carried out swiftly and effectively, at the installers' cost1. She met the UK Minister for Energy Consumers on 22 January to discuss the process to put right the issues identified by Trustmark, and said her officials will receive regular updates from their UK Government counterparts1.
"I would like to thank the UK Minister for Energy Consumers for contacting me about this issue and taking immediate action to suspend installers and protect consumers."
Households affected will receive a letter from Ofgem outlining steps to resolve any issues, the statement says1. The Cabinet Secretary said she knows the news will be concerning to households in Wales that have received solid wall insulation under ECO4 or GBIS, and that she has confidence in the steps being taken to put things right1. The statement does not name the installers suspended, the number of households affected, or the number of properties involved; none of these has been reported1.
The Cabinet Secretary drew a distinction between the GB-wide schemes and the Welsh Government's Warm Homes Nest Scheme, which she said is separate1. Nest includes an independent quality assurance service, with experts checking the quality of scheme designs and visiting installers to inspect their work, including checks on exterior and interior wall insulation projects1. Any issues identified are corrected immediately, before the installer is paid for the work, she said1. For social housing retrofits, she said expert personnel and rigorous processes within partner organisations significantly reduce the risk of poor workmanship by contractors1.
Why it matters for households
Solid wall insulation is one of the more consequential measures a home can take on: it changes how the walls behave, and poor installation can leave a property colder, damper or harder to heat than before, while the household still carries the disruption. For a home's energy independence, the value of the measure rests on it performing as designed over decades, not on the certificate issued at handover. The ECO4 and GBIS insulation failures are therefore a test of whether publicly funded retrofit delivers durable reductions in heat demand, or leaves households to absorb the cost of correction. The statement's assurance that remedial work is at the installers' cost, and that Ofgem will write to affected households, sets out where responsibility is intended to sit1. The installers who carried out the work, and the quality checks that should have caught defects earlier, are central to how much confidence households can place in the schemes going forward.
What happens next
Affected households will receive a letter from Ofgem outlining steps to resolve any issues1. The Welsh Government's officials will receive regular updates from their UK Government counterparts, and the Cabinet Secretary will be kept informed of progress1. No timetable for completing remedial works has been reported1.