Brian George Lewis Mansergh was born in Wynberg, Cape, on 30 May 1897 and died in Cape Town aged 80 on 18 July 1977. He was educated at Rondebosch Boys’ High School and at the South African College School. He studied Civil Engineering (1919-20) at the University of Cape Town. He joined the office of architects Kendall & Morris in December 1920, before leaving to study architecture at the Liverpool School of Architecture in 1922, taking the special war examination of the Royal Institute of British Architects (RIBA) in July 1922, and receiving a certificate in Civic Design as well as Architecture.
Returning to Cape Town, it is likely that he resumed work in Kendall's office. In July 1927, he entered into partnership with FK Kendall, remaining in this firm until June 1932, when he became a lecturer in the Architecture Department at UCT.
He was an associate with CP Walgate on several buildings and was vice-president of the Cape Provincial Institute of Architects from 1932 until 1933 and president of the CPIA 1933-34.
Mansergh continued to practise on his own account in Cape Town. In 1938 he won the Cape Provincial Institute of Architects' Bronze Medal for the Land and Agricultural Bank of South Africa, Cape Town.

Brian Frost was born in Messina to Patrick O'Brien and Enid Frost on 31 May 1928. He went as a boarder to Cordwalles in Pietermaritzburg and he matriculated as a school prefect and head of house at Michaelhouse, after which he enrolled as an engineering student at UCT. His career path changed when he met Brian Mansergh, completely by accident, through a varsity friend who was related to BM. BM was already a respected architect. Brian Frost worked first as a draughtsman and by 1977 he was engaged in design, documentation and supervision of various commissions in both the then Rhodesia and in the RSA.
He had three children, Shaughn, David and Richard but lost his first wife in 1977 to cancer. In the same year, he was appointed by the British department of the environment as their local architect, a job he held for many years and thoroughly enjoyed. For the following eleven years, he raised his children as a single parent, but in 1988 he married Colleen Byrne.
Some of the projects which Brian was involved in were the Land Bank – (he completed extensions after BM's death) - and the PDSA. He loved the challenge of researching the needs which a new project provided. By 1980 Brian had earned the respect of the South African Council of Architects and was granted membership of the Institute.
Many years of commitment and hard work for the British Government earned him an OBE which was bestowed on him in November 1994.
Much of his time was taken up with maintaining the British Residence. In addition he had complete responsibility for buying, selling and renovating the houses required by the embassy staff. He was also engaged in many private projects, one of which was a vast palazzo for the Raimondo family near Hermanus between Hawston and Vermont, called Mudge Point. This was a very big project involving many reception rooms, bedrooms, stables and maids' quarters. Prior to Mudge Point, Brian had renovated his private house in Bishopscourt.
He died 29 June 2009.