View West's agreement to buy the property is conditional on gaining resource consent to demolish the hall, which the company argued was beyond repair.
Council commissioners last year declined this consent and the developer has appealed to the Environment Court.
The hall was built as a Congregational church in 1885. In 1900 it was relegated to hall status after a bigger and grander church was built alongside.
Both buildings have served mainly the Cook Islands community as a Presbyterian church since the 1970s.
The walls of the hall were made of weak concrete using crushed scoria with lime-based cement and are not reinforced with steel.
The Pacific Islanders' Presbyterian Church tried to keep up with maintenance but deterioration of the hall outstripped repairs and in 2012 the council slapped a dangerous-building notice on the hall, the building was closed and fences were put up to keep people out. Timbers were rotting, there were problems with the roof and a report raised the prospect of "catastrophic failure of the walls".
This week, residents in the vicinity received an unsigned notice in their letterboxes which is headed, "Attention Mt Eden residents and parents!!! Dangerous building - major health and safety risk in our community".
It says engineers have recommended a "proper cordon fence" be erected around the hall - up to 10m high and extending 15-20m from the building.
This would block most or all of Esplanade Rd, where the existing wire fence is only about 5m from the building.
The Herald spoke to some neighbours of the site. One family, who declined to be named, expressed only mild concern about the hall.
Another, Eric Zylstra, a retired cabinet maker, dismissed the risk, saying "It's all bollocks", and that he suspected the leaflet came from supporters of the development.
View West could not be reached. Its lawyer, Bianca Tree, was unaware of the leaflet.
Zylstra said the hall should be saved.
"It's beautiful; much nicer than the church. I think the council should purchase these old buildings and restore them as community facilities."
The council's team manager of compliance investigations, Kerri Fergusson, said the council was satisfied the protection zone around the hall was adequate, but had sought an update from engineers.
"The council … may take further action if the engineers' advice is that the zone needs to be extended."
Asked if the hall's demolition might have to be ordered because of its deterioration, Fergusson said: "The heritage team … have advised they do not believe the building needs to be demolished, but that work can be carried out by the owners to make the building safe."
Asked if the council would try to acquire the building and fix it, Fergusson said the owners had been told what could be done to restore and maintain it as an historic building.
