Theophilus Arthur Allen was born in Notting Hill, London, England in 1868. He was articled to his father, Theophilus Allen (1846-1929) in 1885 and remained with him as his assistant. He also attended classes at the Architectural Association in London. He qualified as an architect in 1892 and was elected an Associate of the Royal Institute of British Architects (ARIBA) the following year. He commenced practice as an architect in 1893 and was in partnership with his father.
His address was given as 3 Duke Street, Adelphi, London in 1892 and 1914; Lynethorpe, Normandy, Surrey in 1914; and Littlemead, Wanborough, Wiltshire in 1931. He died in Guildford, Surrey on 18 December 1931
Note: because of the similarity in their names, some of the work attributed to Theophilus Allen may be by Theophilus Arthur Allen
Cottage hospitals at Weybridge and Woking; Sanatorium at Brox; Nurses and children's homes, Chertsey Union; Village homes at Ottershaw and Hayling Island, (or Rt. Hon. Countess of Meath; Schools at Ottershaw, Addlestone, Chobham, and Chertsey; Chancel Trinity Church, West End, Chobham: Theatre Royal, Worthing. London work: 155, New Bond Street; 11-13-16, Orange Street, Haymarket; 184, Queen's Gate, for late George McCullock, Esq.; and residences, &c, for Messrs. A. Essex, W. Dettelbach, R. Lilienfield, A. Levy, Max Friedlander. Mrs. Holt, Mrs. Allison, and others. Country residences, &c: for Sir Henry D. Le Marchant, Bart., Sir Edward Stern, Sir Charles Walpole, Col. C. T. Reay. C. B., Mrs. Pears, and Messrs. J. Coutts Michie, A. Tooth, A. Levy, N. H. Johnson, B. G. Gardner. E. J. Bowering, H. J. Bidwell, H. Hicks, E. J. Addlngton, A. E. Turner, G. H. Dorrell, Julius Berlein, P. H. Savage, L. J. Baker, J. Hume Dodgson, H. J. Greenhill, C. L. Smiles, R. Gibbs, A. R. Cobbett, A. H. Britton, H. E. Paine, W. G. Tarrant, and others; house at Mulsenberg, South Africa, for A. F. Williams, Esq. [Source: Who's Who in Architecture 1914]
Directory of British Architects 1834-1914. Compiled by Antonia Brodie, et al. Volume 1: A-K. London; New York: British Architectural Library, Royal Institute of British Architects/Continuum, 2001
Who's Who in Architecture 1914. London: Technical Journals Ltd., 1914