The cost to redevelop a key building in Wellington's national music centre has blown out to $84 million- more than double the initial estimate.
The state of the Municipal Office Building (MOB) is the final nail in the coffin of seismic issues for Te Ngākau Civic Square.
Last year the Wellington City Council struck a deal with Victoria University and the New Zealand Symphony Orchestra (NZSO) to refurbish and lease the building to the centre for 25 years.
The deal meant the building would become home to the University's New Zealand School of Music and the orchestra.
The centre has previously been pitched as one that would "transform New Zealand's arts scene and inspire future generations".
But Wellington's arts scene is all too familiar with seismic strengthening projects not going to plan: St James Theatre needs double its original budget too.
It's understood the original cost to strengthen MOB was $40m, but the council's shovel-ready project submission to the Government shows that has now blown out to $84m.
The submission said the project was at a detailed design stage, but changing funding priorities threatened the council's ability to go ahead with the redevelopment at that time.
Council chief executive Barbara McKerrow told the Herald the $40m figure was very much an early indicative estimate.
"Since then, far more detailed engineering and QS work has been undertaken. Costs for the building have remained within earlier estimates but analysis of ground conditions mean that foundation works will be more complex than originally anticipated and therefore more costly."
MOB is rated at just 40 per cent of the New Building Standard, meaning it isn't too far off being earthquake prone.
Built in the 1950s, the building's windows, plumbing, heating, ventilation and other features are need replacement.
McKerrow did not directly respond to questions about where the council could find the extra millions or whether consideration was being given to demolish the building altogether.
But she said a detailed report on the final cost implications and other issues was due to be presented to Mayor Andy Foster and councillors by the end of the year.
Victoria University and NZSO confirmed they were aware of the cost escalation, which they said the council has been transparent about.
"All parties, including Wellington City Council, continue to work towards making the world-class national music centre a reality," NZSO chief executive Peter Biggs said.
The university and NZSO are aiming to fundraise $30m for the fit-out of the national music centre.
So far the campaign has received $18.3 million in pledges and is reportedly in a strong position to reach their target.
MOB joins several other buildings in Civic Square on shaky ground.
Next door to MOB, the Town Hall is being earthquake strengthened to the tune of $112m. An initial estimate put the project at just $43m when the building closed in 2013.
The future of the neighbouring Civic Administration Building remains unknown because the council and insurers are still in a wrangle after the Kaikōura Earthquake.
In the meantime, the council is spending more than $3.6m on rent for every year it's unable to return to those offices.
Across the square sits the central library, which was abruptly closed last year and now has a price tag as high as $200m to earthquake strengthen it.
The Herald filed an official information request with the council on July 10 asking for a copy of all correspondence between the three parties involved with the national music centre.
After several inquiries regarding the information's whereabouts, the Herald was told on September 4 the information was before the senior leadership members responsible for the project and pending sign-off.
As of 6pm last night the Herald was yet to receive the information requested three months ago.