Addressing Parliament Sunak said 160,000 “greener” homes could be built on the land, which is collectively equivalent to the size of 2,000 football pitches.
The Chancellor also confirmed a boost to housebuilding in general with increased investment in the sector.
He said: “We are investing more in housing and homeownership with a multi-year settlement totalling nearly £24bn.
“[The government will provide] £11.5bn to build up to the 180,000 new, affordable homes [the country needs annually], 20% larger than the previous program.
“We are investing an extra £1.8bn, enough to bring 1500 hectares of brownfield land into use, meet our commitment to invest £10bn in new housing and unlock a million new homes.”
Third-quarter data shows that new home registrations fell by 27% quarter on quarter to 33,779, while completions dropped by 8% to 31,908.
The government annual target for new homes stands at 180,000 per annum.
Steve Seal, CEO, Bluestone Mortgages, said: “The Chancellor’s commitment to investing in the housing market is welcome news for all, however it needs to be backed by a realistic and credible plan to deliver on the critical need for housing.
“Further government investment to build affordable homes will support the younger generation and low income families locked in rental cycles to take their first steps onto the property ladder, while the £5bn fund to remove unsafe cladding will help prevent homeowners from becoming property prisoners.
“But, speed is of the essence, and we must see the government deliver on these promises quickly.”