The agreement with Lovell Partnerships has been signed off by Mayor Andy Street and will see the homes built over the next eight years, boosting the region's aim for 215,000 new properties by 2031.
It will see a range of schemes focusing on bringing old industrial land back into use, including:
151 homes on land off Steelhouse Lane, Wolverhampton.
283 homes on land off Green Lane, Walsall – including 89 affordable properties and 72 for rent.
225 homes on 12 infill sites on land owned by Sandwell Council.
Plans for 75 affordable homes in Cookley Wharf, Brierley Hill.
A joint venture with Walsall Housing Group to deliver new developments across the West Midlands
Mr Street announced the deal in a keynote speech to dozens of leading public and private sector figures at the West Midlands Forum for Growth conference in Birmingham.
He said: “We have earmarked hundreds of millions of pounds to help transform our brownfield land into thriving new communities that offer affordable, well designed homes for local people, and premises for firms creating worthwhile jobs.
“The West Midlands is undergoing a huge resurgence, with a thriving economy and more and more people looking to take advantage of all our region has to offer.
"However that success brings with it several challenges, not least the need to build more homes and commercial premises to keep up with the demand of residents and businesses.
“This ground-breaking partnership with Lovell will help us to address these challenges by bringing together their expertise with the WMCA’s powers and resources to build more than 4,000 homes on former industrial land.
"This way we can unlock more brownfield land for homes and jobs, and just as importantly protect the precious greenbelt land at the same time.”
The WMCA's housing lead, Councillor Mike Bird, the leader of Walsall Council, said he believed the deal would be "highly effective in speeding up the supply of land, predominantly brownfield, for development".
“It will help deliver attractive schemes that ultimately give everyone the opportunity for a decent home and job," he added.
More than 14,500 new homes were built in the West Midlands last year, the highest number outside London.