Tenants have moved out of an 11-storey office block in central Wellington amid the discovery of a new earthquake risk, despite the building having recently been strengthened.
Eagle Technology House has been assessed against new guidelines issued after the partial collapse of Statistics House in the 2016 Kaikōura earthquake.
Engineers have found the building would have a theoretical New Building Standard (NBS) rating of below 34 per cent, which is what defines a building as earthquake-prone.
This is despite the stairs of the building being strengthened in 2013 followed by further work in 2017, bringing the building up to 80 per cent NBS.
A subsidiary of Cheops Holdings Limited purchased the building in March this year, development manager Nick Wareham told the Herald.
"Some downgrading of the building's seismic rating was anticipated, however not to this extent", he said.
The New Zealand School of Tourism (NZST) has decided to move its operations out of the building after receiving information from the owner last week about the earthquake risk.
"Based on this information, NZST immediately made the decision to discontinue using the building and students were asked to shift to online learning from home while alternative campus facilities were found", chief executive Kylie Wilson said.
"The health and safety of students and staff at NZST is of the utmost importance which is why immediate action has been taken in regard to this issue."
FishServe chief executive Lesley Campbell told the Herald the company has decided to find alternate premises after discussion with the landlord.
Weaknesses were revealed in the hollowcore and floor diaphragms of the building after it was assessed against something called the Yellow Chapter.
This is a proposed revision to engineering assessment guidelines for concrete buildings.
It was issued in November 2018 and reflected what engineers learned from an investigation into the partial collapse of Statistics House.
It's called the Yellow Chapter because it is still being tested to see if it could be incorporated into regulation. So it cannot be used to determine whether a building is earthquake prone.
But it has also proven hard to ignore.
Wellington's central library was closed after it was assessed against the Yellow Chapter and given a theoretical rating of just 15 per cent NBS.
For as long as the Ministry of Business Innovation and Employment is consulting on the Yellow Chapter, there is no legal requirement for building owners to undertake these assessments or subsequently close buildings.
But in the council's case, it decided that morally it did not have a choice.
Engineers found elements of Eagle Technology House theoretically scored below 34 per cent NBS against these guidelines, Wareham said.
Asked about the future of the building, Wareham said: "At this stage we are focusing on completing our engineering investigations and design and will use those to inform our plans for the building,"
Wellington City Council acting chief infrastructure officer Mike Mendonça said the council was in touch with the building owner and working through the issue.
"This is not a building that would normally come up as part of our earthquake prone assessments, however this is a building that did pop up after the Kaikōura earthquake."
Eagle Technology House was one of 80 buildings which underwent urgent assessments following the 2016 Kaikōura earthquake.
The buildings all had similar qualities to Statistics House and the council's Targeted Assessment Programme urgently assessed them for damage.
The most recent strengthening work on Eagle Technology House received a council Code Compliance Certificate on August 14, 2017.