Colin Rowntree was born in Strathbungo, near Glasgow, Scotland on 9 August 1891 and was articled to his father, Frederick (Fred) Rowntree (1860-1927) in Hammersmith, London. He also attended classes at the Architectural Association Day School in London. After completing his articles in 1910 he remained with his father as his assistant until 1914. After war service he returned to his father's practice and in 1919 was made a partner. His elder brother, Douglas Woodville Rowntree (1888-1966) had become a partner in the firm in 1912 as Fred Rowntree & Son. The practice was subsequently renamed Fred Rowntree & Sons. Following the death of their father in 1927 the brothers ran the practice with the name unchanged until at least 1939
Colin Rowntree was elected an Associate of the Royal Institute of British Architects (ARIBA) in 1918 and a Fellow of the Royal institute of British Architects (FRIBA) in 1937.
His address was given as 11, Hammersmith Terrace in 1912 and 1926; Museum Chamber, Museum Street, York in 1930 and 1939; 94 Baker Street, London in 1930; and 9 Wyndham Place, London in 1939. He died in 1965