During the next year, the office building will have three floors added to it, with the cranes being used to lift material up to construction height.
The building's owner, NZ Moray Property Ltd, applied for resource consent in 2004 when a "need for further good-quality office space in the central city" was realised, manager Lynne Ray said.
Adding three storeys, the equivalent of 3000sq m, to the top of a 10-storey building was a "bit of a challenge", Amalgamated Builders construction supervisor Trevor Hart said.
Trying to keep all affected parties happy would be a "major issue", with the builders working with current tenants and retailers in the area to minimise the impact of things such as noise.
Smith Crane and Construction began putting the cranes together on Sunday and hoped to have them completed by tomorrow, Mr Hart said.
