Roger Gunter Simmons [commonly known as Roger G. Simmons] was born in Croydon, Surrey, England on 12 September 1920. Nothing is known about his training as an architect. He was in practice from the 1940s onwards. Between 1947 and 1949 he lived in South Africa. He returned to England in July 1949.
A house in Oxshott, Surrey, England designed by him is discussed in 'Decorative Art' 1958-59 (p.11). In 1968 he designed residential accommodation for the elderly in Brookers Green Lane, Ashstead, Surrey. Simmons was an Associate of the Royal Institute of British Architects (ARIBA).
Simmons served in the Royal Air Force in World war Two. His spitfire was shot down on 24 March 1943 and he spent the rest of the war in Stalag Luft III where he was of the forgery department that made fake documents for escapees. He died in Oxshott, Surrey on 31 August 1975.