A Labour government would insulate all homes that need it within the next decade, Keir Starmer pledged today.
The party leader made the promise in his keynote speech as he warned "action is needed now" to fight the climate crisis.
The plans would be funded by huge public borrowing as part of a £26bn-a-year investment in fighting climate change over a decade.
They appear similar to the Warm Homes For All scheme announced under Jeremy Corbyn in 2019, which also pledged grants for low-income households - and also would have cost £60bn over a decade.
Labour today said the plan would "save families over £400 a year on energy bills" and mean upgrading 19 million homes in a decade, costing £6bn a year from the £26bn pot.

Sir Keir did not give firm details of the pledge in his speech, including how the end date might be changed by the date of an election.
But the party later said it would include:
- Upgrading 19 million homes so that they reach a minimum energy efficiency of EPC Band C
- Providing grants to low-income households and low interest loans to those able to pay to cover the cost of retrofitting
- Supporting up to 500,000 jobs
- Working with local and combined authorities, and the private sector, to recruit and train staff to upgrade housing
- Fitting homes with insulation, double glazing, upgraded home heating systems, and other renewable technologies
Labours' leader told delegates: "The Tories inherited plans from Labour to make every new home zero carbon.

"They scrapped them and now we have a crisis in energy prices emissions from homes have increased and we have the least energy-efficient housing in Europe.
"So it will be Labour’s national mission over the next decade, to fit out every home that needs it, to make sure it is warm, well-insulated and costs less to heat and we will create thousands of jobs in the process.
"I can also pledge that we will also introduce a Clean Air Act and everything we do in government will have to meet a “net zero” test to ensure that the prosperity we enjoy does not come at the cost of the climate."
The speech marked a make-or-break moment for the Labour leader as pressure grew on him to announce his firm vision for the future of Britain.
Sources played down the amount of policy that would be announced in the speech, with the leader focusing on “competence” and drawing a line under the Jeremy Corbyn era.
But a string of top Labour figures demanded more direction from the leadership during the annual conference in Brighton.
Sir Keir did announce plans to hire thousands of new teachers - funded by £1.7bn-a-year more tax on private schools by removing their charitable status.
He promised “the most ambitious school improvement plan ever” to fix an education system battered by more than a decade of austerity.
The party leader also pledged to guarantee mental health treatment within a month for all who need it if he gets into 10 Downing Street.
faced a string of hecklers today during his first ever Labour Party conference speech - including after he spoke emotionally about his mum’s death.
The party leader hit back declaring “shouting slogans or changing lives?”, prompting a standing ovation from his backers, after delegates shouted through parts of his speech.
A single heckler started singing "Oh Jeremy Corbyn" from the balcony, to cries of “oh shut up" from a handful of delegates. Another shouted “it was your Brexit policy!” when he said Labour lost support in 2019.
Other hecklers then shouted “£15!” - a reference to calls for a £15 minimum wage which the leader rejected - as he spoke about poverty pay. He joked: “At this time on a Wednesday it’s normally the Tories who are heckling me.”
The leader was also booed when he joked Sunday - when he pushed through rule changes - was “particularly nerve-wracking”… because of Arsenal’s 3-1 result.
The loudest heckles in the early part of the speech appeared to come from a handful of delegates directly in front of the leader, a few rows back from his podium in Brighton.
They came just after he talked about his mother’s death from Still’s Disease.
They held up red pages and protested at his leadership. What they said was not immediately audible to reporters in the room.