William Flockhart was born in Glasgow in 1852, the son of William Flockhart, tailor and clothier, and Margaret Gibson. There was a family link of some kind to Sir William Flockhart of Duncan Flockhart & Co, Edinburgh, the chemists who developed chloroform. In 1870 he was articled to Adamson & McLeod and took classes at Glasgow School of Art where he was a prize-winner in 1871-72. He presumably remained with McLeod after the dissolution of his partnership with Adamson c.1871-72, moving to Campbell Douglas & Sellars as assistant in 1876-77.
In 1878 Flockhart entered a design in the Brompton Oratory competition in association with the unidentified Gordon as ‘Gordon & Flockhart’. Gordon may have been George William Hamilton Gordon, born 1854, an assistant in the office of Alfred Waterhouse, who was the assessor and placed their design in the final four, describing it as ‘the work of a Master… The interior seems to me to be very nearly perfect’ In the event the final choice lay with the Fathers who chose Herbert Gribble who had made designs for them in 1874-76.
After a year of study in London and Paris in 1878-79, he entered the office of William Wallace at 27a Old Bond Street, London, first as an assistant and then in partnership as Wallace & Flockhart, his earliest commission being the addition of a tower and spire to Newhaven Free Church where Sir William Flockhart was a member of the congregation.
On 9 September 1880 he married Christine Lochhead at her home, 33 Granville Street Glasgow, the minister being A A Bonnar of Finnieston Free Church, on which he had worked when with Sellars, his own address being given as 15 Marlborough Place, St James Wood.
Flockhart’s clients tended to be either artists like Ricketts, Charles Shannon and John McWhirter and the photographers Elliot & Fry or extremely rich like his principal clients James Douglas Fletcher of Rosehaugh, Stuart Samuel, Samuel Montagu, Sir Edmund David, diamond merchant, the art dealer Joseph Duveen and Sir Frederick J Mirrielees of the Union Castle Mail Steamship Company. For the Union Castle Company he designed the interiors of S S Balmoral Castle in 1910. He was also consultant to the Derwent Valley Water Board and designed the architectural elements of the Derwent and Howden dams.
Flockhart was an extremely inventive and scholarly designer, something of a trial to the staff as designs were endlessly changed and perfected, sometimes after work was well under way. Goodhart Rendel described him as ‘an extremely sensitive draughtsman’, and ‘potentially the best of the lot’.
The partnership of Wallace & Flockhart was dissolved c.1883, Flockhart continuing to practise alone. He was admitted FRIBA on 18 February 1901, his proposers being John Belcher, John McKean Brydon and Ernest George.
Flockhart appears to have taken his former senior assistant Leonard Rome Guthrie into partnership as Flockhart & Guthrie by 1912. He died on 10 April 1913, leaving moveable estate of £29,631 6s 2d. He had one son who did not become an architect and two daughters, one of whom married Guthrie, who inherited the practice.