Landlords whose properties received external wall insulation under the government’s energy efficiency schemes must be vigilant for official letters regarding faulty work, as the scheme funding faces a sudden and controversial cut.

A National Audit Office (NAO) report has revealed a staggering figure: 98% of homes fitted with external wall insulation (EWI) under the government’s ECO4 scheme need remedial work to fix serious defects that could lead to damp and mould.

Action Required: Look Out for Ofgem Letters

The National Residential Landlords Association (NRLA) is urging landlords to take immediate action, as official notification letters about sub-standard installations will be sent directly to the affected property.

• Alert Tenants: Landlords should proactively tell their tenants to look out for a letter from Ofgem and inform them immediately upon its receipt.

• Grant Access: The government is calling on anyone who receives an audit invitation to allow qualified professionals access to the property so that problems can be identified and fixed.

• Guarantees: The government has confirmed that even if the original installer is no longer operating, the work under ECO4 or the Great British Insulation Scheme (GBIS) should still be covered by guarantees, and installers were pledged to fix defects free of charge.

Despite these pledges, repair progress remains slow: only 2,900 homes had been fully repaired by mid-September 2025.

Policy Cliff Edge: ECO Scheme Scrapped

The news about faulty repairs is compounded by a major government policy shift: Chancellor Rachel Reeves confirmed in the Autumn Budget that the ECO scheme will be scrapped in March 2026 to save money on energy bills, to be replaced by the Warm Homes Plan.

While the new Warm Homes Plan—which aims to help homeowners cut energy costs and offers grants for heat pumps—is welcome, the abrupt termination of the £1.3 billion ECO funding has drawn sharp criticism from industry experts.  “Suddenly yanking £1.3 billion in funding is chaotic and has created a cliff edge for thousands of low-income households in fuel poverty, as well as small and medium-sized enterprises (SMEs) employing some 10,000 people,” said Anna Moore, CEO and founder at retrofit consultancy Domna.

Moore argued that the “brutal cut” to a successful scheme risks “losing the installers, coordinators and surveyors” whose expertise is critically needed. She concluded that an extension to the ECO scheme is essential to allow for an orderly transition to the Warm Homes Plan and prevent the sector from having to rebuild capacity “from scratch.”