Harold Boas was the younger brother of Harold Krantz’s mother Isabel. When Krantz was young he saw some of his uncle’s work and decided that he too wanted to become an architect. Boas moved to Perth in June 1905, transferring to the Western Australian Institute of Architects. After working with a few different architects he eventually became a partner with Oldham, Boas & Ednie-Brown.
Some of Boas’ early work in Perth included the King's open-air picture theatre in 1905, a warehouse for printer and stationer Sands & McDougall Ltd, and the Nedlands Park Hotel in 1907. Later he worked on projects as diverse as aircraft hangars, radio station premises, bulk-storage wheat silos, the Emu Brewery, Adelphi Hotel, Gledden Building, and various churches and private homes. His style was more ornate than the utilitarian, functional style Krantz would later adopt.
Just ten years after his arrival in Perth Boas was representing the South Ward on the Perth City Council. From 1914 he was a member of the Town Planning Association and by the late 1920s he was chairman of the Metropolitan Town Planning Commission. It was at this time that Krantz found himself unemployed in Adelaide and his uncle was able to provide him with work in Perth.
In 1931 Boas became the first president of the Town Planning Institute of Western Australia and an inaugural member of the State division of the Town Planning Institute of Australia. Shortly after this Oldham, Boas & Ednie-Brown was also impacted by the Depression and with little or no work, was forced to close. Krantz moved on having learnt much from his early years as an architect and within a couple of years was able to open his own practice.
Boas continued with his political aspirations and worked for the Federal government in Melbourne during World War Two before returning to Perth. He was also heavily involved in Jewish matters both local and national, a role that understandably stepped up following the Second World War. Boas continued to practice as an architect and take a role in public life until late in life, and enjoyed long hours debating the finer points of architectural design with his nephew Krantz.