Karl Vernon was born in Neuenahr, Rheinland-Pfalz, Germany on 19 June 1880. By the early 1900s he had moved to England. During World War he served in the Royal Army Medical Corps and was awarded a Military Medal. He worked as an architect and as an interior decorator., and was employed for part of his career with London County Council A scheme for the decoration of a dining room designed by Vernon is illustrated in 'The Studio Yearbook of Decorative Art' 1907 (p.72).
Vernon was a Member of the Society of Architects (MSA). When the Society of Architects amalgamated with the Royal Institute of British Architects in 1925, he was admitted a Licentiate of the Royal Institute of British Architects (LRIBA).
Vernon was also a rower and competed with the British team at the 1912 Summer Olympics in Stockholm.
His address was given as "Six", Eton Avenue, New Malden, Surrey in 1923, and Trellis House, Park Road, Chiswick, London in 1926. He died in Worthing, West Sussex on 11 July 1973.