The Historic Places Trust and the Culture and Heritage Ministry have both accepted that the earthquake-prone Harcourts building cannot be saved.
But while the trust acknowledges the building cannot remain in its present state, it is fighting for the historic facade and foyer to be retained in a new redevelopment.
Consultants' reports prepared for the two agencies say it would cost nearly $11 million to strengthen the 84-year-old office block building in Lambton Quay, and the best use of the property would be as a redevelopment site.
Reports by engineering consultant Win Clark and Colliers International valuers are included in submissions to the application by property developer Mark Dunajtschik to demolish the building.
Wellington City Council is to hear submissions next month.
The nine-storey block, originally built for T & G Insurance in 1928, is listed as a category 1 heritage building.
Mr Dunajtschik wants to demolish the building and replace it with a 24-storey block behind a lightweight replica of the present facade.
The new block would be an extension of the adjoining HSBC Tower.
Historic Places Trust senior heritage policy adviser Robert McClean said it was opposed to total demolition of the building but "it could accept partial demolition in conjunction with a new building on the site".
A category 1 listing is reserved for buildings that the trust believes should be kept in their entirety. It now accepted that was not an option, Mr McClean said.
"We can't just leave buildings standing and not bring them up to speed.
"Public safety is important, so that means the facade has to be strengthened in some manner."
The trust wanted to see the foyer retained and for any new building on the site to be set back behind the facade.
- The Dominion Post
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