National Grid and Berkeley Group have launched a new joint venture to develop major residential and mixed-use development schemes across London and the South East of England.
The new joint venture called St William will use National Grid's development expertise as well as Berkeley's design, construction and marketing expertise to build properties on brownfield sites.
With more than 20 sites in London and the South East, National Grid has the potential to provide in excess of 14,000 homes in the next ten to 15 years.
The initial phase of the project will see construction of around 7,000 homes, including 2,000 allocated for affordable housing and related developments, such as schools.
National Grid and Berkeley will hold an equal share in St William, which has available funds of up to £700m, and will finance it through a combination of shareholder equity and bank funding at an equity-to-debt ratio of 50:50.
National Grid chief executive Steve Holliday said: "By bringing together Berkeley's development expertise with National Grid Property sites, we hope to transform redundant land that was once at the heart of the industrial revolution to meet the housing and commercial needs of the 21st century."
St William intends to begin development activity on the first site in 2016, with the first homes scheduled to be completed in 2017.
Berkeley Group managing director Rob Perrins said: "This is good news for home building.
"St William will take these sites and turn them into new communities. I am delighted to be working with a partner like National Grid which shares our values and has such a strong pipeline of land and assets."