The stores shed / engine shed was a single storey building orientated E-W, constructed, according to the plans held by J. W. Greaves and Sons Ltd prior to 1939. On a plan of c.1955 reproduced in J. G. Isherwood 1988 'Slate from Blaenau Ffestiniog' the stores shed is labelled as an engine shed. Remains of the shed are visible on 21st Century aerial photographs in amongst small spoil tips created by driving a modern access road to Diffwys Slate Mill (NPRN 415671).
References:
Plans referred to are held by J. W. Greaves and Sons Ltd, Blaenau Ffestiniog.
J. G. Isherwood 1988 'Slate from Blaenau Ffestiniog', AB Publishing, Leicester, p.36.