In article ,
Christian McArdle wrote:
A lot of "modern" building practices started to be more widely used
in the 1930s, but didn't become almost universal until later. I can
think of plasterboard and cavity walls for two more.

Marley concrete roofing tiles - which probably were talked of with
derision by many 1930's roofers but have outlasted many clay ones of
similar vintage.

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Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm