London street full of derelict mansions ‘has space for 300 homes’

It is one of Britain’s most expensive streets, earning the moniker “Billionaires’ Row”. Yet The Bishops Avenue in north London also has mansions that have been left derelict for decades. Now, some of Britain’s leading architects have drawn up plans for building hundreds of affordable homes on the avenue. According to designs drawn up by firms including Mae, which last month won the Stirling prize, the UK’s most prestigious architecture award, there is room for up to 300 homes on one site. The proposals have provoked questions about how soaring land values, offshore property ownership and weak national and local planning powers have deepened England’s housing crisis. Last week, the Local Government Association said the number of unoccupied homes in England had risen by nearly 60,000 since 2018, to more than a million properties. In the past decade, the housing waiting list in the London borough of Barnet, where The Bishops Avenue is located, has more than tripled to more than 3,000 households – part of a 1.2 million-household queue for social housing across England that is at its highest level since 2015. The current owner of the prime three-hectare (7.4-acre) site is an Isle of Man-registered company whose beneficial owner is listed as a Cypriot businessman who gives a Dubai address. It has permission to build luxury apartments likely to sell for more than £200m with zero affordable housing. The council’s policy is to demand at least 35% affordable housing on new developments, but the owner’s agents negotiated cash contributions of £2.5m to its housing fund instead – equivalent to the price of a single flat. The site has fallen into ruin since the early 1990s when nine Saudi-owned mansions were left empty. The Guardian revealed the mansions’ state in 2014 when it gained access to the properties and found crumbling swimming pools, collapsing ballrooms and ferns growing out of sweeping staircases. Since then three mansions have been reduced to rubble and this summer a fire destroyed the roof of the largest, the Towers. At the request of the Guardian, architects drew up designs for affordable housing. Alex Ely, the founding director of Mae, drafted a plan for 240 one-, two- and threebedroom apartments around a new arts centre, preserving the Towers under a glass structure. Another architecture practice, RCKa, estimated that up to 300 homes could go on the site, with a mix of social and privately rented flats and family homes dotted among trees. “Is it right there should be land like this sitting in a ridiculously expensive part of London that is unused?” said Russell Curtis, RCKa’s founding director. “At the moment we don’t have policy levers to do anything about it.” Without national land use reforms, the schemes are likely to remain on paper. Ely said councils should be given stronger powers to seize vacant sites using compulsory purchase mechanisms. Ross Houston, Barnet’s cabinet member for homes and regeneration, said he wanted “greater powers to intervene when it’s clear homes are just an asset”. He said: “There are genuine issues about whether local authorities should be given more compulsory purchase powers as part of making sure areas do not become blighted by lack of development. “In Bishops Avenue … a lot of the sites are owned by companies that may well be registered in the Cayman Islands or wherever else and it’s quite hard to keep track of.”