Yes, there was a 1929 canopy at the Savoy Hotel in London (UK).
For details, go to the Nickel Devolopment Institute web site at
Their 44 page publication 11023 (from 2001) called
Timeless Stainless Architecture describes 16 different buildings. It
can be ordered by snail mail or downloaded as a big (1.76 Mb) .pdf
file. They have lots of other publications on architechtural use of
The book Architectural Metals notes that Pittsburgh Plate Glass had an
earlier stainless roof that was built in 1924.
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