Ritu Saha is on waking watch. After work, the university administrator comes home to guard her block of flats in southeast London against fire until midnight. Two years after Grenfell Tower was engulfed in flames, killing 72 people, Saha and her neighbours still live in a building that is wrapped in three types of flammable cladding.

“Let’s walk,” says Saha, 43, who is dressed in a hi-vis vest, and we start to scour the 10 storeys at Northpoint, in Bromley, for signs of smoke or heat. For the past 18 months, this has been carried out every half-hour, night and day. At first it was done by agency staff — then residents saw the bills. Now they volunteer for some shifts, but it still costs