Irwin George Smith was born on 8 November 1889. It is not known where or with whom he trained as an architect. He was qualified in the early 1920s and was elected an Associate of the Royal Institute of British Architects (ARIBA).
A design for a house by him was entered in The "Daily Mail" Ideal Houses Competition for Architects, 1927.
From the early 1930s he was a partner in the architectural firm J. M. Shepherd & Partners]
His address was given as The Pantiles, Watford Road, Sudbury, Middlesex in 1923 and 1927; 13 Elms Lane, Wembley, Middlesex in 1930; 38 Bedford Place, London in 1930 and 1939; 15 Sudbury Court, Harrow, Middlesex in 1933 and 1939; and 32 The Glen, Green Lane, Northwood, Middlesex in 1967. He died in Southhall, Middlesex on 6 May 1967