Herbert Dewes Pritchett was born in Darlington, Durham, England on 18 May 1859. He was articled to his father, James Piggott Prichett (1830-1911), in Darlington from 1877 to 1882, and remained with him as clerk of works. He was then clerk of works to Alfred Waterhouse (1830-1905) and Paul Waterhouse (1861-1924) of Waterhouse & Son; to Brightwen Binyon (1846-1905); and to Barry Parker (1867-1947) and Raymond Unwin (1863-1940) of Parker & Unwin. Pritchett commenced practice as an independent architect in 1900 in Darlington and was in partnership with his father from 1900 to 1911. He was elected a Licentiate of the Royal Institute of British Architects (LRIBA) in 1912 and a Fellow of the Royal Institute of British Architects (FRIBA) in 1926.
His address was given as 12 High Row, Darlington, County Durham in 1912 and 1933. He died in Worthing, Sussex on 25 March 1945.
(In partnership) Extensive alterations to Grimstone Manor, Yorks; large additions to British and Foreign Training Coll., Darlington; Pease & Sons' Offices, Darlington; alterations to Holy Trinity Church, Darlington; New Church, Coekerton Darlington; restorations and oak panelling to St. Cuthbert's Church, Darlington; alterations and decorations to private chapel at Raby Castle; several houses, Darlington; various roads on Estate of Lord Barnard at Darlington. (Own works; from 1911): Tower to Leeming Church. Yorkshire; oak seating, St. Paul's Church, Darlington; extensive alterations to Brettanby Manor, near Darlington; extensive alteration! to large shop, Darlington; houses at Beverley and Darlington; drill-hall, &c, Hartlepool.
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