Wave 3 of the Warm Homes: Social Housing Fund (WH:SHF) defines its scheme launch as the date on which the final set of Wave 3 guidance documents were published in September 2024, according to the scheme guidance1. Draft guidance for the scheme had been published on Monday 13 May 2024, and the application window closed at midday on 25th November 20241.
The scheme funds energy efficiency upgrades and low-carbon heating measures to homes in England1. Wave 3 was originally allocated £1.29bn for delivery from April 2025 to March 2028, with the Warm Homes Plan announcing a further £295m of grant funding available through the scheme in the 2026/27 financial year1. Grant funding may be drawn down from 1st April 2025 and must be spent by 31st March 2028; lead grant recipients must spend all their grant funding by that date and will lose their opportunity to claim after it1. From 1st April 2025, lead grant recipients will be able to draw down up to 20% of their total grant funding award for eligible costs incurred in putting together Phase Requests, which should all be submitted by 30th September 20271.
The delivery window for Wave 3 will run to 30th September 20281. Grant recipients were previously permitted to continue delivering their projects using co-funding for six months after the end of the grant funding window, until September 2028; in light of the additional funding this has now been extended, allowing grant recipients to continue delivery using co-funding until March 20301.
"Scheme launch is defined as the date on which the final set of Wave 3 guidance documents were published in September 2024."
The guidance sets out several changes to eligible measures. Domestic batteries installed to be used alongside solar PV panels were included as an eligible measure in June 2025, a pause on battery installations was announced in November 2025 because no Microgeneration Certification Scheme (MCS) product standard was in place, and grant recipients may resume installation of domestic batteries as of 2nd February 20261. Air-to-air heat pumps are not eligible until they are able to be certified by MCS, which the guidance expects to happen in 2026, and heat batteries will not be eligible until they can be MCS certified1. MCS consulted on a Thermal Energy Storage System Standard in March 2025 and announced a pilot in September 20251.
| Measure | Status under Wave 3 |
|---|---|
| Domestic batteries with solar PV | Eligible again from 2nd February 2026 |
| Air-to-air heat pumps | Not eligible until MCS certification, expected 2026 |
| Heat batteries | Not eligible until MCS certified |
| PCM heat batteries for hot water | Not installable; no recognised SAP category or approved modelling convention |
| Sensors and monitoring technologies | Eligible where modelled in RdSAP/SAP |
Why it matters for households
The scheme pays for fabric and heating work in social housing, so the practical effect for a tenant is that upgrades to a home's insulation, heating or solar depend on their landlord holding a grant funding agreement and delivering within the window. The dates matter because grant funding must be spent by 31st March 2028, while co-funded delivery can continue to March 20301. For homes receiving solar panels, the battery position determines whether stored electricity can be added: installations resumed on 2nd February 2026, and the guidance states batteries should only be installed where it drives energy bill savings for the household, with a check on whether a preferable time-of-use tariff is available and a functioning smart meter present1. Homes in areas earmarked for heat networks face a separate policy: Heat Network Zoning is expected to be implemented as a national policy programme in 20251.
What happens next
Phase Requests should all be submitted by 30th September 2027, grant funding must be spent by 31st March 2028, and the delivery window runs to 30th September 2028, with co-funded delivery permitted until March 20301. The guidance states DESNZ will communicate to grant recipients in advance of any further requirement coming into effect, and that it will not retrospectively require compliance with a future standard1.
Sources1 cited
- WH:SHF Wave 3 Scheme Guidance, assets.publishing.service.gov.uk