Churchill proposed them in March 1944, before the war had ended. The Housing (Temporary Accommodation) Act went through Parliament the same year. The target was 300,000 prefabricated homes within ten years, built in factories and shipped out to bomb sites, edge-of-town fields, and anywhere else that could take them. The country managed 156,623. It was the fastest mass housing programme in British history.

The houses were meant to last ten years.

Most had a built-in refrigerator, unusual for 1946, when many permanent homes still relied on a pantry and the milkman. Flush toilets indoors. Hot water from an immersion heater. A fitted kitchen, essentially. The scheme delivered factory-made domestic convenience in emergency housing assembled in aircraft factories and shipyards from timber, asbestos cement, aluminium, and wood wool.

The Uni-Seco Mk3 was one of the main models: 29,000 built, timber-framed, steel windows, asbestos cladding. You can still find them. The Excalibur Estate in Catford has the largest surviving cluster — 189 bungalows put up in 1945 and 1946, many of them assembled by German and Italian prisoners of war still awaiting repatriation. Around 700 survive in the Bristol area. Others are scattered from the Isle of Lewis to the south-west. Individual prefabs around the country have been Grade II listed.

The ten-year deadline kept being extended. Councils needed the housing stock. Residents, who had been given something strange — a private house, with a garden, for council rent — refused to leave. Some have stayed in the same prefabs for more than seventy years.

The hauntological register is unusual. Most abandoned buildings are haunted by a future that was supposed to last and didn't. Prefabs are the inverse: a temporary future that quietly became the actual past. The "permanent" houses that were to replace them got built too, went up in towers and estates, and in many cases came down before the prefabs did. Trinity Square in Gateshead lasted forty years. The Heygate is gone. The Aylesbury is going now. The Excalibur prefabs were still being lived in while the Heygate was being demolished — temporary housing outlasting its replacement.

Lewisham has been tearing Excalibur down in phases since 2013, though the six listed bungalows on Persant Road remain. Six houses out of 189. A kind of settlement: most of it goes, a token survives.

The Prefab Museum ran a temporary exhibition at 17 Meliot Road in 2014. Former residents came back with photographs and letters from decades of campaigns against demolition. Most of the estate has come down in the years since. The listed row on Persant Road is what's left.

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