The Dunedin City Council-owned building - built in 1878 - has been sitting vacant for more than three years, since the Otago Art Society quit the site to move to the Dunedin Railway Station.
The doors have remained closed despite a deal signed last June, when the council agreed to lease the building to the Otago Museum to use for conferences, functions and exhibitions.
There have been few signs of progress since then, and council community and recreation services manager Mick Reece told the Otago Daily Times questions were being asked about the "pretty prominent piece of real estate".
"Why's it still empty? Why isn't anything happening?"However, Otago Museum chief executive Shimrath Paul said he did not think planning for the site was taking an "unduly long" time.
The museum was working with the New Zealand Historic Places Trust and its own architects to complete a conservation plan and finish the design of the building's refurbishment, which would provide more space for functions, exhibitions and other uses, he said.
Those plans would need to be completed and approved by the NZHPT before they were costed, and the results then approved by the museum's board, before work could begin, he said.
"Inside it's a mess. It really needs a big revamp. Before you touch anything, the architects need to have it run past the NZHPT and have a conservation plan done, which we had to work through. So that's where it is at still.
"There's a number of things that need to happen before we even put a spade in the ground."
The deal with the council provided the building rent-free to the museum until January 1 next year, when the museum would begin paying $12,000 annually for 33 years.
A staff report to a meeting of the council's community development committee last year said the building's future use was integral to the long-term redevelopment of the museum reserve.
The museum had planned to spend about $1 million upgrading the building, including installing a lift, while ensuring the work was "in sympathy" with the building's category two listed status, the report said.
However, Mr Paul said fundraising for the project would also be required, and he could not say when work with the NZHPT - which began late last year - would be completed.
Nor could he say whether he expected the building to be open by January 1.
"That's the aim ... everything else being equal and all going well.
"It isn't like there really is a timeframe we're really working to ... when it gets done, it gets done."
