Established by the King Edward VII Welsh National Memorial Association "for the intensive investigation of observation cases and for the treatment by modern methods of chronic and advanced pulmonary disease", it was built between 1932 and 1936 and officially opened by Prince George, Duke of Kent as a specialist tuberculosis facility in 1936.
As at Paimio, the use of a concrete structural frame enabled the use of wide windows, proving the patients with sunlight, fresh air and views.
In 1943 there was a Battalion of American Seabees, the US Construction Corps, living on a merchant vessel tied up in Penarth docks, while they built a large number of Quonset huts for a rapid temporary expansions of Sully Hospital needed for the extra wartime pressure of additional patients, both military and civilian.
[5] While standing vacant the hospital building was briefly considered as a potential location for the temporary housing of up to 750 Eastern European asylum seekers, but those plans were eventually shelved after a campaign and objections by local residents.
[6] In the early 21st century the building was converted into individual luxury apartments by the investment property company Galliard Homes.