ECO4 has ended. The Warm Homes Plan is the government's successor scheme, with billions set aside to fund insulation and heating upgrades for eligible households. Here is what you need to know.
ECO4, the government scheme that funded free insulation and heating upgrades for eligible households, came to an end on 31 March 2026. In its place, the government has launched the Warm Homes Plan: a broader, longer-term programme with a planned budget of around £13.2 billion over this parliament. This guide explains what has changed, who can benefit, and what the process looks like for South London households.
The Warm Homes Plan is the Labour government's flagship home energy improvement programme, introduced as part of its clean energy mission. It replaces ECO4 and is designed to upgrade the energy efficiency of millions of homes across England, with a focus on low-income households, fuel-poor properties, and homes with low EPC ratings. The government has set a target of upgrading five million homes over the course of this parliament.
The Warm Homes Plan is delivered through several strands. The two currently live are the Warm Homes: Local Grant, for owner-occupiers and private renters, and the Warm Homes: Social Housing Fund, for social housing providers. A private rented sector strand is expected to follow.
The Warm Homes: Local Grant is the main route for households in South London to access funding. It is administered by local authorities, meaning Lambeth, Wandsworth, and Southwark each hold their own allocations and manage referrals directly. The grant is aimed at low-income owner-occupiers and private renters living in properties with an EPC rating of D or below.
Measures that can be funded include:
As with ECO4, the grant can cover the full cost of improvements for eligible households, with no contribution required in many cases.
Eligibility criteria under the Warm Homes: Local Grant are broadly similar to ECO4's LA Flex route. Households do not need to be receiving benefits to qualify, but must be on a low income or identified as fuel poor by their local authority. The property must also have an EPC rating of D, E, F, or G. Properties already rated A, B, or C are unlikely to be eligible.
Each local authority has some flexibility in how it applies the criteria. If you are unsure whether you qualify, the best first step is to contact Lambeth, Wandsworth, or Southwark council's energy or housing team, or to speak to an accredited retrofit assessor who works regularly with local grant schemes.
As under ECO4, a PAS 2035 Retrofit Assessment is required before any funded work can begin under the Warm Homes Plan. This is a mandatory part of the process and cannot be bypassed. The assessment surveys the property's fabric, heating system, ventilation, and moisture levels, and produces an Improvement Measures Report that sets out which works are appropriate and in what order they should be carried out.
This sequencing matters. Installing insulation without first addressing ventilation or damp, for example, can cause condensation and structural problems. The PAS 2035 standard exists to ensure improvements are carried out safely and effectively, protecting both the occupant and the public investment in the property.
Private landlords in South London should be aware that the Warm Homes Plan includes provisions targeting the private rented sector. The government has indicated that Minimum Energy Efficiency Standards for rented properties are expected to tighten in the coming years, with a proposed minimum EPC rating of C for new tenancies. Landlords with properties currently rated D or below may be able to access Warm Homes funding now to bring properties up to standard ahead of any regulatory change.
The process is similar to ECO4. A Retrofit Assessment is carried out by an accredited Retrofit Assessor. The resulting report is used to design the funded works. An eligible installer carries out the improvements under the oversight of a Retrofit Coordinator. For households approaching the scheme through a local authority, the council will typically manage the installer referral. For households approaching an assessor directly, the assessor can help identify the appropriate funding route.
Carn Energy provides ABBE-accredited PAS 2035 Retrofit Assessments across Lambeth, Wandsworth, and Southwark. We work with local authorities and installers operating under the Warm Homes Plan, and can carry out assessments for homeowners and landlords at any stage of the process.
To find out more or book an assessment, visit our Retrofit Assessment service page or contact us for a same-day response.
ABBE-accredited, TrustMark-registered PAS 2035 Retrofit Assessments across Lambeth, Wandsworth, and Southwark.
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ABBE-accredited EPC assessments across Lambeth, Wandsworth, and Southwark.
