He was born in Portobello, Dublin. Hi family moved to Birmingham when he was a child. He was educated at a CBS school, and at the age of 12 he took his first job in Birmingham as a brass and copper wire packer. While in Birmingham he was a member of the Gaelic League, played hurling, and was a champion step dancer. Summerfield returned to Dublin in 1911.
In 1923 Summerfield opened his own company, F.M. Summerfield Ltd., and was the agent for American Chrysler cars. He started assembling Chrysler's in 1933 at his factory on Castleforbes Road, after the introduction of the requirement that all cars sold in Ireland had to be assembled there.
He was an unsuccessful candidate at the 1925 Seanad election. A Peace Commissioner, Summerfield served as an independent member of the Seanad, representing the interests of the motor industry. He was also president of the Society of Irish Motor Traders in 1923 and 1924, and the Irish Motor Agents Association from 1924 to 1925. He served as president of Dublin Chamber of Commerce in 1950.
Summerfield's other business interests included the first neon sign manufacturer in Ireland and he was part owner of the Irish Cutlery Company. He married Nora O'Brien (1888–1944) in 1913 and they had three daughters.