Property developer Jon Leng said the roof of the building at 386 Princes St collapsed on Friday some time between 2pm and 4pm.
The cave-in happened one building over from Mr Leng’s apartment in the redeveloped Empire Hotel.
The collapse did not come as much of a surprise to him, but when he was speaking to the Otago Daily Times on Saturday he said he believed the building’s owner was unaware of the recent damage.
The building is owned by Totara-Dunedin Properties Ltd, which is associated with several Christchurch addresses.
Directors of the company were approached by the ODT through a shareholder, but no response has been received to a request for comment.
Mr Leng went on to say the Dunedin City Council had 10 years to ensure something was done with the building as it was leaking and there was a partial collapse of an internal wall.
He believed winter storms last week were the final straw for the property.
Now, stress on the heritage facade was apparent, he said.
Freshly flaked plaster and a broken window were visible from the street.
Hundreds of pedestrians walked past the building each day and Mr Leng was concerned someone could be killed in a collapse, despite the council fencing off the area directly in front of the facades.
The collapse could happen at any time, Mr Leng said.
Squatters had lived in the building, and if they had been in there when the roof collapsed on Friday they would have come out in body bags, Mr Leng said.
An offer he made to buy the six-building lot six months ago had been rejected, he said.
Instead, the present owners appeared to be waiting for the building to fall into disrepair so they could develop the site without paying to preserve the facades, Mr Leng said.
While he had no problem with building developers doing what they needed to do to make money, it was not acceptable to put people at risk.
Even before the most recent collapse, the building had been so dangerous workers could not go inside.
Now the buildings, including the historic facades, were likely beyond repair, Mr Leng said.
He wanted the owners of the lot to do something with the building or sell the property to someone who would do something with it.
It was also hard to believe the council had let something like that happen, given the number of permits that had to be sought for even the most mundane building work, Mr Leng said.
A council spokesman said the council was warned about the condition of the buildings at 380 and 386 Princes St, including that they were in a state of partial collapse, after receiving an engineering report commissioned by the buildings’ owner in early June.
The buildings received dangerous building notices and as a precaution the footpath outside the buildings was closed and a safety cordon installed, the spokesman said.
The council would contact the owners of the buildings this week and require them to provide an updated report about the safety of the buildings.
The owner had been given six months to carry out any work needed to address the danger to the public and surrounding buildings, the spokesman said.
In 2009, the ODT reported tenants at 386 Princes St were given two weeks to leave after the council issued a "notice to fix" when an engineer’s report found the building was dangerous and earthquake-prone.