In 1923 he employed Lawrence Harrower Smart to represent the firm as job architect on site for Bermuda Cathedral.
In 1926 the Edinburgh office relocated to 4 St Colme Street on the Moray Estate in the west end of the city.
[5] In 1938 he succeeded George Washington Browne as Royal Fine Art Commissioner,[6] a role he served until death.
[7] In 1944 Tarbolton & Ochterlony became part of the architectural advisory panel for the North of Scotland Hydro-Electric Board, along with Reginald Fairlie and James Shearer.
[8] He died of a cerebral thrombosis at his home, 3 East Castle Road in the Merchiston district of Edinburgh on 31 July 1947.