Nothing is known about Donald McIntire's training as an architect. He possibly studied at Durham University. In 1926, with Reginald Annandale Cordingley (1896-1962) he formed the architectural partnership Cordingley & McIntire. The practice had offices in Durham and Manchester. They designed several churches, mainly in the north-east of England. They also designed the Central Library in Chelmsford, Essex (1935); eight houses in Sale, Cheshire (1936); gas showrooms in Durham (1940); Durham Johnston School in Durham (1952); and Maiden Castle Sports Hall, Durham University (1962-65). The eight houses they designed in Sale are discussed in Small Houses £500-£2500, edited by H. Myles Wright (1937 pp. 82-84). The practice was dissolved in 1969.
From 1935 to 1969 McIntire was the Durham Cathedral architect and was responsible for designing the Miner's Memorial in the south aisle of the cathedral in 1947. In 1948 he designed a factory for the Armstrong Cork Company on the Team Valley Trading Estate in Gateshead