Fearn was a British-born, Wellington-based architect with a long career spanning a large part of the 20th century and incorporating a wide range of styles. He was still working as late as the 1960s.
Most of Fearn;'s work was domestic, but he designed a range of buildings, both in the capital, where he designed over 70 buildings, and further afield. In Wellington he is best known for the William Booth Memorial Training College in Aro Street (1913), which he designed with Austin Quick. This building won the first ever gold medal from the NZ Institute of Architects in 1927.
Fearn's houses include the Frederic Wallis House, Lower Hutt, the grand country house Rototawai, near Featherston, New Zealand, 82 Bolton Street as well as houses in Hobson Street, Thorndon. He was involved in the rebuilding of Napier and Hastings after the Hawkes Bay earthquake and among his surviving designs is the former Bestall's Building, Napier (1932).[2] His son Detmar was also an architect.