zinc-roofhttp://www.oed.com/dictionary/zinc-roof_n%3Ftab%3Dmeaning_and_usezinc roof, n.
First published 1921; not fully revised

zinc roofnoun

S. Afr. and W. Indies.
  1. 1883–
    A corrugated roof of galvanized iron.
    1. 1883
      The zinc roofs of the out-buildings, the stone walls of the ‘kraals’, all reflected the fierce sunlight.
      O. Schreiner, Story of African Farm vol. I. i. i. 11
    2. 1946
      There was a mass of dry maize leaves under a zinc roof jutting out from the wall.
      U. Krige, Way Out vi. 82

Originally published as part of the entry for zinc, n.

zinc, n. was first published in 1921; not fully revised.