Born in Northamptonshire in 1921, Penn had a grand upbringing, attending Eton before studying history, and then architecture, at Trinity College Cambridge.
Penn moved to the US shortly after graduating, where he worked with Richard Neutra in Los Angeles, and later with SOM in New York, before moving back to Britain to settle in Suffolk.
Architectural historian Richard Gray thinks Penn's most renowned works are his nine houses in Suffolk, all with flat roofs.
Gray said: 'Penn never gained much publicity, as it wasn't really there at the time. He was strongly influenced by Mies van der Rohe, and was one of few people at the time who applied the Classical design of Roman villas, with their symmetry and formality, to Modernist design.'
An exhibition displaying Penn's work is opening at the end of March at the Margaret Howell Gallery in London's Wigmore Street, which hopes to bring his architecture to a wider public.
John Penn: born 11 March 1921 died 14 February 2007.