At 17 he was articled to architect Cecil Wood but before his time was complete war broke out and he served four years as wartime aide-de-camp to New Zealand's governor, later governor-general, Lord Liverpool.
[1] In the 1919 King's Birthday Honours, Helmore was appointed a Member of the Order of the British Empire, for services as aide-de-camp to the governor-general.
He returned to Christchurch and set up his personal practice in February 1923 winning some substantial commissions.
[1] They designed Isaac House, which was built in 1926 and is registered by Heritage New Zealand as a Category II structure.
[6] He designed the Canterbury Pioneer Women's Memorial at the top of the Bridle Path that goes from Lyttelton to the Heathcote Valley.