Born in Melbourne, Australia, Treeby was educated at St Stephen's Church of England Grammar School in Melbourne where he was dux in Euclid and Algebra. He went on to the Melbourne Technical School in 1876, studying architectural drawing under EW Braske, and passed his RIBA final examination in 1886. During this period he was articled to Osgood Pritchard. He married in 1881 aged twenty-one. He apparently completed his architectural studies in England. Treeby practised for about five years in Australia where most of his work, amongst it a brick kiln which collapsed, was done in Brighton, Victoria between 1890 and 1894 when he left for South Africa.
In 1895 Treeby arrived in Johannesburg where he 'became associated with WH STUCKE. The following year he received an appointment as architect and chief engineer to two important commercial corporations' (Afr Archt Sep 1912:48), which were the German Mining and General Business Companies for whom he designed a number of buildings, including a brick factory, the Silesia Buildings (1896) and the General Mining Building (1903-1904). In 1896 he won a gold medal for architectural drawing and perspective 'against architects from the Cape Colony, Transvaal, Free State and Natal' (FRIBA nom papers 1927). It is not yet known in which event he won this prize but was acclaimed for his 'powerful and brilliant draughtsmanship' (Afr Archt Sep 1912:48.) In 1898 he won the competitions for the design of the Kaffrarian Natural History Museum (now Amathole Museum), King William's Town.
During the Anglo-Boer War Treeby served in the Rand Rifles, firmly on the side of the Reformists since he mentioned in his FRIBA nomination papers of 1927 that he had taken part in the Jameson Raid. Legend has it that he was a spy and reputed to have disguised himself as a nurse to escape capture on one occasion. He apparently made his way into Boer forts making drawings of their layouts and selling these to the British for £20, 000 (Lewis 1986). A hardly credible story but apparently, after the war, Treeby received the congratulations of Sir John Ardagh and Sir W Everett on behalf of the British Intelligence and Ordnance Department for his services during the war.
In 1901 Treeby was listed working as an architect in Cape Town in partnership with CH EDWARDS (cf. TREEBY & EDWARDS) but had returned to Johannesburg by 1902, entering into partnership with Charles ABURROW (cf. ABURROW & TREEBY) in 1903; the partnership lasted until the middle of 1922. Thomas Cullinan became an important client about this time and in 1903 Treeby was appointed director of Cullinan's Consolidated Rand Brick, Pottery and Lime Company at Olifantsfontein, laying out the brick and lime factory. He was director for a year, an 'expert in the manufacture of bricks, tiles, lime and cement'. In association with William LECK he designed the Cullinan Building in Johannesburg (1904-1905), demolished in 1966, as well as brick factories for Booysens and Auckland Park, Johannesburg, all before 1912. Again in 1903, Treeby is said to have been sent to London to find a suitable architect for the proposed Anglican Cathedral in Johannesburg (Baker 1979:4) and is said to have suggested George Fellowes PRYNNE for this job. Treeby had an active if not always fruitful career. In 1904 he won the competition for St Augustine's Church in Doornfontein, which he duly executed in natural stone and 'designed in the Gothic Style, in which he is an enthusiast' (Afr Archt 1912:48.) Together with his partner Aburrow, he acted as supervising architect for the architect of the firm of English decorators and builders Waring & Gillow TH SMITH on the Consolidated Buildings in Johannesburg (1904-1906), a building which, according to Van der Waal (1972:68), marked the arrival in Johannesburg of the American skyscraper concept of the 1890s. At about this time Treeby may have travelled to Italy since attention was drawn to such a visit in respect of the detailing of John Orr's building in Pritchard St (1905/1906 cf ABURROW & TREEBY) 'designed from actual sketches made by Mr Treeby during his time of study in Florence' (Afr Archt Sep 1912:48.)
After the depression of 1906-1908 and in partnership with Aburrow, he was placed fourth in the competition for the Johannesburg city hall (1910) and second in the competitions for the Johannesburg abattoirs (1910), for the Natal University College, Pietermaritzburg (1910) and for the South African Party building (1919) in Johannesburg. The partnership between Treeby and Aburrow having been dissolved in 1911, Treeby won the competition for the Trades Hall, Johannesburg in 1912 on his own and appears to have expanded: 'Mr Architect Treeby has a considerable amount of work in Durban' (Afr Archt Nov 1913: xi.)
As President of the Transvaal Institute of Architects from 1912 to 1913 he read papers on 'Brick Making', 'The National Bank, Bloemfontein' and on 'Lime Making' at meetings of the Institute. Treeby enlisted for service on the outbreak of the First World War, gaining the rank of Major and acting on the side of law and order during the Miners' Strike of 1922.
In 1927 the well-established architect JS DONALDSON wrote an appreciative description of Treeby's design for Mosenthal's Warehouse: 'the elevations are boldly conceived and abundance of window spaces are obtained without destroying the symmetry and architectural design. The lower storeys are of cut stone, the upper ones being faced with Klompjies (thin Dutch bricks). The main features are octagonal pilasters (enclosing constructional steel columns) and the heavy cornice with consuls of reinforced concrete projecting six feet. The mouldings and enrichments are confined to the cornices and corner features and the details of the same are simple and refined' (Treeby's FRIBA nomination papers 1927.) The building was selected for the display of South African architecture at the 1924 Wembley Exhibition by a committee of the Transvaal Institute of Architects.
Treeby's fortunes seem to have slumped about 1912 since the family moved from the large propertied suburb of Houghton to the more modest suburb of Auckland Park where his address in 1927 was at Woodside in Lothbury Road, Auckland Park, Johannesburg. A move to Durban came soon after (n.d.) where he lived at 43 Bellevue Road in Isipingo Beach. He died in Addington Hospital, Durban.
ATA 1909; Pres TPIA 1912-3; FRIBA 1927; ISAA 1927; NSA, London (?). (Afr Archt Sep 1912:48 port; Afr Archt Nov 1913: xi; Cartwright 1977; FRIBA nom papers (1927) 2547; Lewis 1986; Juta's CT dir 1901:321; ISAA mem list; NAD MSCE 25438; SAAE&A, proceedings, vol 4 1897/98:183; SAAR May 1937: 239 obit; SAWW 1908, 1910)
All truncated references not fully cited in 'References' are those of Joanna Walker's original text and cited in full in the 'Bibliography' entry of the Lexicon.