For people living in blocks of flats that did not have basements (or had basements that could not accommodate all residents) the local authority would build surface shelters. These shelters, often built onto the road, were of brick with a concrete slab roof. There is evidence that some these structures (in London especially) were poorly constructed and that the roofs were far too heavy for the walls. There were also occasions when the shelters were misused if they were not locked (being used as a lavatory, for example).
The below image shows a policeman viewing a street that has surface shelters and suffered from bombing in September 1940.
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