Walter George Whincop was born in Hackney, Middlesex [now London], England in June 1888. Between 1906 and 1909 he worked in the office of Alfred Conder (1845-1931). He trained as an architect under Farrow & Fletcher and Hobday & Venning. He also attended the Evening School of Architecture at University College, London, where he was awarded the 1st Prize (Design) in 1912. He was also awarded the Carpenters' Company Travelling Studentship in 1913.
From 1909 Whincop worked as an assistant in the London County Council Architects' Department. He qualified as an architect in 1912 and later that year was elected an Associate of the Royal Institute of British Architects (ARIBA). In 1912 he was in partnership with Harold Albert Thomerson (1889-1948) in Stoke Newington, London. Drawings and plans of a house designed by them are illustrated in Designs for One Hundred Ideal £1,000 Houses. Being copies of the hundred best designs entered in the 1912 Daily Mail Architects' Competition (1912 p.116).
In the 1930s he was District Surveyor for Hackney West, and Interim District Surveyor for Stoke Newington.
Whincop's address was given as 13 Charing Cross Road, London in 1912; and 74 Filey Avenue, Stoke Newington, London in 1912 and 1914; 14, Weatholm, Hampstead Garden Suburb, London in 1923 and 1926; and 133 High Street, London and "Westholm", Wades Hill, Winchmore Hill, London in 1939. He died in Wood Green, Middlesex, on 20 November 1961
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