SA/NT Freemasons Deputy Grand Registrar and City of Adelaide councillor Henry Davis said he hoped the proposed $400 million “Keystone” tower will be a tourist magnet for Adelaide and that it will encourage visitors to stay in the city longer rather than only travelling to the regions.

He said the 183-metre-tall building will house a 240-room hotel, a three-storey public viewing platform, and the new Adelaide Museum of South Australian History (AMOSAH), which is supported by the History Trust of South Australia.

“A lot of the commerce and potential tourism that we have essentially goes off to the regions, which is great, but we also have everything from cute pandas to a bloody space agency here in the city of Adelaide,” he said.

“The idea behind Keystone is to act as a catalyst, or a lightning rod, to bring tourists to a central point and then go out and explore Adelaide and then our regions as well.”

The Freemasons’ Grand Lodge was built in 1927 and was added to the State Heritage Register in 1984.

The current proposal comes after several attempts to develop the site in the past.

The proposed development has received pushback from members of the “Help Save South Australia’s History from Demolition” Facebook page due to concerns around the height of the building and the loss of heritage, with the page administrator stating that the proposed tower is unsympathetic to the streetscape of North Terrace and writing that “a State Heritage protection should be something, and not be used as a bargaining tool to line the pockets of a select few”.

Davis said he understands heritage concerns around the loss of the Great Hall but the proposed development is necessary to repay the Freemasons’ debt, including the $350,000 to $500,000 that currently goes to maintenance costs each year due to the deteriorating state of the building.

The current estimated cost of restoring the building is around $8 million.

“I personally love the Great Hall, and that’s what will be demolished out the back,” Davis said.

“It’s a beautiful hall. However, by allowing us to remove that hall and then build the tower, what that means for Adelaide is then that we can restore and maintain not only this tower, but also all the other heritage sites around.”

Among the issues he identified were render dropping off the side of the building, “concrete cancer”, falling damp, and water damage on the roof.

Davis said that architects had looked at options to retain the Great Hall, such as building over it, or deconstructing and reconstructing it, but that this was considered too expensive and too difficult.

He also acknowledged concerns around the height of the proposed development but said that it was necessary due to the difficulties of the site.

“One of the issues, for example, is that the main conduit power cable for SA Power Networks actually runs directly under this building,” he said.

“It’s a confined site with difficult access points, as well as the heritage implications of the front building, which make it an extremely challenging site.”

Davis said that the Freemasons have heavily consulted with their membership about the proposed development and that there will be a vote in early June to decide whether to proceed with the plans or not.

He also said there would be a “public consultation” on July 1, where he hopes to present the case for the development to the wider community.

The Keystone Tower, if built, would be the first in Adelaide to exceed 150-metres in height – the widely accepted definition of a skyscraper.

A separate plan lodged by a Sydney developer for a 180-metre-tall skyscraper on the corner of Pulteney and Flinders Steet was approved by the State Commission Assessment Panel last September.