The concert where a balcony collapsed injuring 18 people should never have been held at student flats, Dunedin Mayor Dave Cull says.

A report released by the Dunedin City Council yesterday revealed the balcony - which tenants of the Castle St flat agreed would have no more than eight people on - was "critically overloaded", causing the joists to give way and resulting in 16 or 17 concert-goers plummeting 3m, landing on others below.

Two people were seriously injured, with University of Otago student Bailley Unahi still in Burwood Hospital in Christchurch with serious spinal injuries following the incident.

Sixteen others suffered minor injuries during the Six60 concert last month.


The report clears the building's owner of wrongdoing and says the balcony, constructed in 1999, was built to design and code for the time.

However, Mr Cull said the concert should never have been held at a student flat. "A silly, single tragic decision to hold the event in the wrong place has led to some pretty major consequences for some of those there," he said.

An email to the band's management was unanswered as of late last night.

Mr Cull said Six60 needed to take responsibility for its organisation of the event.

"They would have been endeavouring to encourage as many people as possible to get in there," he said.

"It's a residential area. It's not the right place for that. The management of the band should have thought of the possible consequences of holding that concert there.

"They kept it reasonably under wraps, so you would have to ask why they did that."

The report recommended testing the remaining intact joists from the balcony, investigating the effects nails had on the structure's integrity, appointing a timber expert to assess the quality of the joists, referring the report to the Ministry of Business, Innovation and Employment (MBIE) - which were also investigating the collapse - and forwarding to the drafting committee examining possible updates to the building code.

The University of Otago said, in an emailed statement, it supported the recommendations in the report.

Council general manager services and development Simon Pickford said the balcony was built to code and the building had consent. "While it's important to know the balcony was built to code, the key issues centre on the event itself and where it was held," he said.

The council had already suggested the property's owner seek engineering advice and strengthen the other balconies.

The report said a different loading standard for balconies, particularly in the student precinct, could be imple-mented if MBIE changed the law.

Mr Cull was also supportive of strengthening the building code in relation to student housing.

He also mooted establishing rules which governed events in the student quarter. "We need to consider having some protocols," he said.

The council would continue to work with the university, police and the Otago University Students' Association to improve student safety and behaviour, he said.