London is starting to build more council homes

TO THE UNTRAINED eye, the small football pitch and bumpy grass mounds between two post-war council flat blocks in Bells Garden estate do not look like much. To Lewis Schaffer, a professional comic from New York who lives nearby, they are the front line in a battle with Southwark council. If the council gets its way three new blocks will soon fill the space. Mr Schaffer sees this as the height of stupidity. “You wouldn’t build on Central Park, would you?”

London’s councils were once big housebuilders, building the majority of new homes in the capital in the 1960s and 1970s. Sadiq Khan, the mayor, wants a return to past glories. He promises 10,000 new council homes by 2023, funded by a £1bn ($1.4bn) investment pot. Things are heading in the right direction. Last year councils started on 3,156 residences, up from 454 in 2015. They are building at their fastest rate since the early 1980s.

To do so, they have to overcome two obstacles. One is a lack of land. Some 85% of the capital is built on and the remaining slivers are mostly parkland or protected by the “green belt”. Thus councils are left with little option other than to slot houses on their own land. The low-hanging fruit is unused bits of existing estates, says Tom Copley, the deputy mayor for housing.

Such an approach requires little demolition of existing...