The Tees Valley Combined Authority has opened bidding for £33.3m to build 1,085 homes on brownfield land across the region, the latest round of a programme aimed at sites that would otherwise stay derelict.

Mayor Ben Houchen and cabinet members approved the package on 31 July, and the authority is inviting developers to register interest this month, with a detailed plan for the homes due before leaders later this year.

The money comes from the Brownfield Housing Fund, backed by the Ministry for Housing, Communities and Local Government. It pays for remediation and enabling works, clearing contamination and putting in access and services, while developers deliver the housing on the prepared sites. The authority says it agreed the locations with Homes England and the local councils.

The barrier these sites face is financial rather than physical. "The main barrier is financial viability," said Matt Forrest, chair of the Tees Valley Housing Partnership. "We're an area with low land and property values, and the cost of cleaning up brownfield sites can be very high." Forrest estimates the region's brownfield land could hold close to 9,000 homes, which places this round at roughly a ninth of the long-term opportunity.

The fund has a track record. Earlier rounds supported more than 1,500 homes across 11 sites, including 296 at Hillside Gardens in Middlesbrough with housing group Thirteen and homes on Hartlepool Waterfront with developer Jomast.

Mayor Houchen said the money would "make the most of brownfield land across Teesside, Darlington and Hartlepool to create the homes local people need, while protecting our green spaces."

The figures show how much public support this kind of regeneration needs. The £33.3m works out at about £30,700 a home, spent before a brick is laid, to cover remediation and enabling works.

That is the measure of the gap between what these low-value sites cost to prepare and what finished homes recover. The public purse covers that gap, and developers build on top of it.

Two questions will show whether the approach scales. The open call will reveal how many sites come forward at this level of support, and the business case going to leaders later this year will set out where the homes land and how many are genuinely new rather than already consented. The answer will show whether this is a one-off round or a route Teesside can repeat.