Roy Keith Binney was born at Auckland on 13 April 1885, the 10th and youngest child of George William Binney and his wife, Mary Mather. The Binney family was of some standing in Auckland where the auctioneering firm of G. W. Binney and Sons dealt in wool, hides and kauri gum. Roy attended King's College, Auckland, from 1899 to 1903, where he played in the First XV. His father died in 1907 and in May 1908 Roy left on an extended visit to England with the intention of studying architecture.
In England he joined the group of pupils in Edwin Lutyens's office. Commissions in the office included the British pavilion for the 1911 international exhibition in Rome, later rebuilt as the British School at Rome. Binney was made an associate of the school in 1913. Binney exhibited a single drawing at the Royal Academy of Arts in 1912.
He returned to Auckland, and in November 1914 was registered as a practising associate of the New Zealand Institute of Architects. In December he was appointed visiting architect for the Auckland Architectural Students' Association; he later became vice president. He was listed as an honorary member of the Auckland Society of Arts in the same year. For the students' association Binney organised and supervised competitions that helped transmit the lessons he had learned in London. He also practised on his own account. His first Auckland building was Guisnes Court, a large two-storeyed house for his mother, now 532 Remuera Road. Designed round a spacious salon, it pays obvious tribute to Lutyens. Across the road a smaller house, 493, was again strongly influenced by Lutyens.
In early 1916 Binney left again for England, where he was commissioned in the Royal Field Artillery and sent to France. He was wounded in 1918. Back in New Zealand in 1919, he went to live with his mother. He opened an office in Swanson Street, and received commissions from A. McCosh Clark (39 Bassett Road), Leonard Horrocks (88 Lucerne Road) and prominent businesswoman Amy Hellaby (542 Remuera Road). Houses undertaken in 1924 and 1925 included one for Binney's sister Georgina Clifton (178 Remuera Road), one for Frank Mill (4 Upland Road), and others for his mother (a smaller house, 6 Tirohanga Avenue, which may have been a speculative investment) and for his brother Frank (118 Long Drive).
Binney's work is noted for its feeling for space, its skilful detailing, the elegance of the colour choices and the careful selection of materials. Several of his houses featured shingle cladding contrasting with brickwork. Roof lines and prominent chimneys sometimes dominated exterior appearances as they did with Lutyens's houses, and he enjoyed and repeated Lutyens's eccentricities of style.
Binney's mother died in 1925 and Guisnes Court was put up for sale. Trouble over extra costs on Amy Hellaby's contract and, apparently, the threat of disciplinary action by the Institute of Architects decided Binney to leave New Zealand again. In May 1927 the Architectural Review published an article on his New Zealand houses. In 1928 he sent a nephew plans for a house, never built, which bore a strong resemblance to 118 Long Drive, the least typical and most conventionally Georgian of all his houses.
No other involvement with architecture in England is known. Binney served as a lieutenant in the British Army during the Second World War. He never married, and died at Cheltenham, Gloucestershire, on 28 October 1957. He had influenced a whole generation of Auckland architects and brought to the city's domestic architecture a greater sense of style than had previously been evident.