Wellington's Municipal Office Building - since 1956 the home to the City Council and the planned future home for a National Music Centre - is looking set to be demolished.
The building was given an earthquake rating of between 35-45 percent in 2012, and it is believed a new assessment would show it to be less.
A 25-percent New Building Standard (NBS) or less classifies a building as earthquake prone.
The initial plan was to strengthen the building up to 67 percent NBS (New Building Standard), but the cost of doing so rose from $50 million to $84 million.
That would require between $1.5 million and $3.8 million to be taken out of rates each year, for 35 years.
The cost of a new build was believed to be less than that, while the associated market rents would be higher.
Victoria University Wellington and the New Zealand Symphony Orchestra are in a non-binding agreement with the City Council to enter into a 25-year lease for the floors above ground level.
The council report however does not estimate how much a rebuild would cost but only describes it as "no more than option to strengthen and refurbish".
However, $750,000 has now been included in the 2021-2031 Long Term Plan to cover the demolition costs.
The building does have heritage values, as part of the Civic Centre Heritage Area. However, the building itself is not a listed heritage building.
"[This is] a really exciting opportunity for us to say 'we want to put a stake in the ground, we want to get on with this, it is the heart of our city','" mayor Andy Foster said.
"There are challenges in terms of affordability, but that is why we need to be looking at partnerships.
"It's why we need to have other people involved, in helping us to redevelop Te Ngakau Civic Square."