In a joint statement today National Grid and Berkeley Group said the partnership, to be named St William Homes, "brings together access to a significant portfolio of brownfield land owned by National Grid Property in key areas of housing need with Berkeley’s expertise to design, build and market new developments".
The statement said that National Grid has over 20 sites in London and the South East with the potential to provide over 14,000 homes over the next 10-15 years.
In its first phase, St William aims to develop more than 7,000 new homes, including over 2,000 affordable homes.
The joint venture said it will have funds available of up to £700 million, making it one of the top ten house-builders in Britain by turnover.
It aims to commence development activity on its first site in 2016, with the first homes being delivered in 2017.