Career
During the first half of the 20th century, Mahoney was the leading architect in Guelph, Southwestern Ontario. Among the many buildings attributed to him, Mahoney designed several Carnegie libraries in Ontario: Aylmer, Campbellford, Elmira, Exeter, Fergus, Forest, Fort Frances, Kingsville, Midland, Parkhill, Portuguese Hope, Stirling, Tillsonburg, Watford, and Whitby. Mahoney brother, Harry, was the town mayor in 1935-1936.