John Bruce Merson was born in Innerleithen, Peebles, Scotland on 29 August 1870 and was articled to George Gordon Jenkins (1844-1923) and George Marr (c.1846-1899) of Jenkins & Marr in Aberdeen from 1886 to 1890. He also attended Gray's School of Art, Aberdeen and King's College, London. He worked as an assistant to George Joseph Frisch in London in 1891; to John Giles (?-1900), Albert Edward Gough (1842?-1908) and John Evelyn Trollope of Giles, Gough & Trollope in London from 1892 to 1899; and to Willesen Urban District Council Architects' Department from 1899 to 1902.
Merson commenced independent practice as an architect in 1902 and from 1909 worked as an assistant to Alfred Griffin. He was elected a Licentiate of the Royal Institute of British Architects (LRIBA) in 1910 and a Fellow of the Royal Institute of British Architects (FRIBA) in 1927. His address was given as 7, High Road, Kilburn, London in 1902; 17, St Swithin's Lane, London in 1908; 17 Ironmonger Lane, Linden and 4 Park View, Brisbane Road, Ilford, Essex in 1910 and 1911; 9 Lennox Gardens, Ilford, Essex in 1920; and 1929; "Neukullen", Ruskin Drive, Crofton Park Estate, Orpington, Kent in 1938; and 21 Northumberland Avenue, Romford, Essex in 1949. He died in Essex on 3 December 1949. His death was registered in Romford, Essex
For the Ilford Urban District Council (Surveyor's Department) carried out a new Administrative Block for Isolation Hospital; School for 1,200 scholars at Becontree, Essex; Maternity Home
Directory of British Architects 1834-1914. Compiled by Antonia Brodie, et al. Volume 2: L-Z. London; New York: British Architectural Library, Royal Institute of British Architects/Continuum, 2001