The 12 Mosman houses that are making way for up to 100 new apartments

It’s not every day that a stranger will come knocking on your door to convince you to sell your house so they can build a multi-storey $750 million apartment complex.

But that was precisely what happened six months ago when 12 home owners in Sydney’s well-heeled suburb of Mosman were approached by a developer keen to demolish the properties to make room for an amalgamated 5368 square metre site.

The sale was finalised three months ago. A block of between six and eight storeys with 80 to 100 apartments will be built, subject to local council and state government approval.

The 12 properties on Brierley Street and Rangers Avenue in Mosman to be stitched together have an average value of $4.36 million and an average land size of 472 square metres each, according to Domain.

The houses on 27 Brierley Street and 44 Rangers Avenue are the highest valued, at $6.16 million and $6.02 million respectively, while the home with the lowest valuation is 25 Brierley Street, at $3.15 million.

Arissa Group declined to answer when asked about the cost to acquire the homes. All 12 owners declined to comment when approached by the Herald.

Gigalots – or “supersites” – have become an increasingly common phenomenon across Sydney, spurred by state government changes to planning controls, aimed at increasing low-to-medium density near transport hubs and town centres. Suburbs where neighbours have previously united to sell include Cremorne, Rose Bay, North Strathfield, Northbridge, Double Bay and Belfield.

Many suburbs are feeling the clash between the push for greater housing and the desire to maintain their character, with the latest example being the contentious plans for rezoning around a future Woollahra train station. Mosman is no exception, with the suburb being home to a resident who has launched a landmark legal challenge against the government’s housing reforms.

Frank Scarf, director of developer Arissa Group, said convincing owners to sell when they were not planning to do so was difficult.

“Sometimes there’s a lot of pushback. But no one sells if they don’t want to sell – it’s completely their choice and their decision,” Scarf said. “So once you get the group on board, it’s just a matter of whether you can provide or meet their expectations.”

The proposed apartment building will have undercover parking, a gym, and a swimming pool, and is 500 metres away from Cremorne town centre and two kilometres from Mosman’s strip of shops on Military Road.

Scarf said the proximity of the 12 homes to the CBD, and potential water views from level two and upwards, were what drew him to the site, and hopes it will be attractive to professionals and young families.

The developer is considering lodging it as a state-significant development, which would streamline building approval processes. Scarf confirmed 15 per cent of the building would be allocated to affordable housing, so the project is eligible for eight storeys instead of six under the government’s bonus height allowances for state-significant developments.

The proposed development has met backlash from neighbours who feel blindsided by the sale.

Neighbours speaking on the condition of anonymity have labelled the potential apartment an “eyesore” that will worsen traffic and alter the character of the streetscapes.

“Development has to fit with the feel of the area. It needs to go hand in hand with proper planning so it doesn’t put additional strain on infrastructure,” one person said. “It destroys the community we’ve built.”

Another said: “It’s not about affordability, it’s about developers making the biggest profit they can under the guise of affordable housing. They’re going to walk away loaded, having destroyed the area.”

The government’s housing reforms, which seek to address housing shortage, also include specific targets for each local government area across Sydney. Mosman has been set a goal of 500 homes by 2029 – lower than other inner-city councils such as the 5900 target in North Sydney and 2400 in Waverley.

Mosman Mayor Ann Marie Kimber said the council was aware of the sale but was yet to receive any proposals.

“One of our key priorities is to work collaboratively with the state government and our community on managing increased housing density in appropriate areas of Mosman. This must involve proper consideration of infrastructure, transport, amenity and meet the need for housing for key workers and families,” she said.

Since the mid-rise housing reforms came into effect in February, Mosman Council planning records show two mid-rise development proposals have been lodged, including a $43.9 million plan to turn five homes on Awaba Street into a six-storey apartment building with 29 units.

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