Staff at Australia's domestic spy agency ASIO have still not moved into their new $680 million headquarters in Canberra a year after it was officially opened.

ASIO's 1,800 staff were due to move in in September last year, but may now have to wait until the end of this year, 1.5 years behind schedule.

The five-storey building, named after former prime minister Ben Chifley, who established ASIO in 1949, has been plagued by construction delays and controversies.

Its current cost is 9 per cent above original estimates.

In 2011, a 19-year-old man spent 36 hours at the bottom of a concrete basement at the construction site after illegally entering the premises.

The man scaled a low fence and fell nine metres down a concrete basement while the site was empty on a Saturday night.

When he was found by workers on Monday morning he was taken to Canberra Hospital with severe head injuries.

Sorry, this video has expired Watch Michael Brissenden's story: ASIO’s $680 million building still empty (Image credit: Lukas Coch, AAP)

In February 2012 the building had to be evacuated when about 20 glass panels fell from the main entrance and smashed to the ground.

No-one was injured but the ACT construction union said it was not told about the incident for days.

Later in October the building lost another large plate glass window.

There have been serious issues with fire-proofing the building, as well as with the air conditioning.

In May last year the construction union said close to 100 sub-contractors and suppliers had not been paid for their work at the site.

In a statement the Federal Government said the managing contractor for the project Lend Lease was responsible for dealing with each of the sub-contracts.

Then prime minister Kevin Rudd and attorney-general Mark Dreyfus tour the ASIO headquarters in July 2013. ( AAP/Fairfax Media Pool: Andrew Meares )

The ABC's Four Corners program reported last year that the building's blueprints had been stolen in a cyber attack believed to have been mounted by hackers in China.

Then prime minister Kevin Rudd opened the new building in Canberra last July, when it was not yet complete.

"In a world of change, new threats are constantly emerging or evolving - cyber threats, terrorism at home and abroad and people smuggling," Mr Rudd said in his speech at the official opening.

"The technology-dependent world we now live in also presents more challenges and threats. Australia now operates in a world of complex systems, all vulnerable to malicious cyber activity.

"The end of the Cold War did not end the threat of espionage and terrorism. We depend on ASIO to protect our democratic freedoms, to deal with terrorism and to combat espionage."

Surveillance cameras are seen outside the new ASIO headquarters in Canberra. ( AAP: Lukas Coch )

ASIO director-general David Irvine said at the opening that staff were looking forward to moving in to the building.

"We've been spread over a number of buildings in Canberra and this is an opportunity to consolidate our facilities, our info, technology and our people all in the one place," he said.

Currently the building remains behind temporary barbed wire fences and barricades.

The ASIO building will eventually house the Australian Cyber Security Centre and will be dedicated to countering new threats.