Wooden dwellings like chicken houses.

"And the bombed sites where the plaster dust swirled in the air and the willow herb straggled over the heaps of rubble; and the places where the bombs had cleared a larger path and there had sprung up sordid colonies of wooden dwellings like chicken houses?" (Orwell 3).

In 1940, London was bombed by the Germans during World War II. Much of London was knocked out; whole streets of classic architecture were demolished in large areas of London. When Orwell wrote 1984, in 1949, much of London was still being rebuilt, or had been rebuilt as modern buildings, looking out of place and futuristic among all the 19th-century houses around them. The house I lived in in London was actually on a street like this--our half was all new tenement buildings and modern wooden flats, and the other side of the street was all beautiful 19th-century brick houses. Adding this one piece of reality into the book 1984 makes it seem more real, like something that could happen in the future, and not-very-distant either, judging by the title. This means that Orwell was legitimately afraid of this happening, he could see uniformity already taking over the new parts of the town and was frightened.

http://www.eyewitnesstohistory.com/blitz.htm