The Coalition government project to cut its bureaucracy's unused floorspace has solved an expensive headache by filling departmental offices at the flashy Nishi building that once sat half empty.
Public servants have filled thousands of square metres in offices across the capital after the federal government moved them into wasted space in its leased buildings.
Finance Department officials expect the pile-in of bureaucrats into the Nishi building will cut $65 million by filling 14,000 square metres at the upmarket New Acton digs.
Government offices in the building have taken on several federal agencies, but previously sat half empty despite being purpose-built for the Department of Climate Change and leased by the agency in 2012 for 15 years at $158 million.
When the department was disbanded in 2013, the lease went to the Department of Industry and from July 2017, the Department of Communications and the Arts took over under the Coalition project to reduce its unused space.
Bureaucrats from Communications and the Arts, Austrade and Safe Work Australia moved in under the program, dubbed "Operation Tetris". About 75 per cent or more than 14,000 square metres of the Nishi building's office space houses federal agencies despite criticism from the Coalition in opposition when the then-Labor government moved the Climate Change Department into the high rise.
Safe Work expects to finish filling its 112-staff space after a round of hiring. Austrade can fit only eight more staff in its 251-person capacity office and Communications and the Arts has room for 32 more public servants in a space that can house 574.
Colliers director of government services Michael Ceacis said offices that lost public servants under the Coalition project had multimillion dollar upgrades at 17 Moore Street in the city and 38 Sydney Avenue in Forrest, although he didn't reveal the figure.
More than 24,000 square metres of offices in Woden also became vacant as the Veterans' Affairs Department left its 13 Keltie Street offices for the Gnabra building in the city, and the public service commission in 2017 moved from Furzer Street, Phillip to the Treasury building.
The Shared Services Centre, in charge of back office support for agencies, moved to Garema Court and left 10,000 square metres vacant across four offices in Mort, Moore and Marcus Clarke streets in the city.
Most of the government's expected savings from "Operation Tetris" are expected to come from the Environment Department's move into the parliamentary triangle's John Gorton building, vacating 9100 square metres at its old Allara Street offices in the city, estimated to bring $129 million in savings.
Finance also expects major savings from Veterans' Affairs move from Woden to the city ($33 million) and the Jobs and Small Business Department's move into Garema Place in the CBD ($42 million).
Finance Minister Mathias Cormann has defended his department's original estimate of $300 million in savings from the project after the national auditor blew up its methods for reaching the figure on Tuesday. Senator Cormann said its latest calculations revealed a greater saving of $322 million.
Correction: A previous version of this story said 10-14 Mort Street in Canberra's CBD had a multimillion dollar upgrade. The building was 17 Moore Street in the city. Due to an error in an audit report, it also incorrectly said the Digital Transformation Agency freed nearly 4000 square metres by leaving 221 London Circuit office for 50 Marcus Clarke Street.