The Commercial dry docks, located at the north-west corner of Roath Basin (NPRN 305754), was originally constructed as a graving dock by the Bute Dock Company. It measures 600ft (182.88m) long and 60ft (18.288m) wide. By the early twentieth century, the dry dock had been surrounded by various warehouses, lairs, and offices. The Commerical Dry Dock came into the ownership of Great Western Railways in 1922, but by the 1940s was back under the control of the Dock Authority. In 1907, new pumping equipment was installed, but the further replacement of this equipment was delayed by the Second World War after which time newer electrical pumping equipment was installed.

(Sources: British Transport Commission, South Wales Ports (Cardiff: 1948), p. 84; Hutton, An Illustrated History of Cardiff Docks (Great Addington: 2008), p. 88)
A.N. Coward, RCAHMW, 02.08.2018