Months of sometimes tense talks with key councils have bolstered a signature NSW government housing policy, with six sites added to a list of transport zones earmarked for high-density housing.
But one of the 13 affected local government areas, which is also the most well-off, has vowed to continue fighting the changes, arguing they would be "highly destructive" to its leafy upper north shore community.
Train stations at Belmore, Lakemba and Punchbowl in southwestern Sydney, Cardiff and Cockle Creek in Newcastle's west and Woy Woy on the Central Coast have been added.
Dwelling density within 400 metres of 37 stops will be dramatically upgraded in a bid to tackle the state's housing crisis and stop younger residents leaving.
Premier Chris Minns says the reforms - involving the largest rezoning of land in Sydney's history - will deliver more than 170,000 homes across the city and the Illawarra, Hunter and Central Coast regions over the next 15 years.
"If we don't build more houses, young people will up and leave because they can't afford a home ... and if we lose our young people, we lose our future," he told reporters on Friday.
The additions came after several local councils put forward their own suggestions for sites to be fast-tracked for development, he added.
The policy was announced in December as part of broader planning changes designed to add much-needed housing stock.
All but one of the 13 affected councils engaged with the planning department to deliver more housing, the state government said.
Ku-ring-gai Council, covering a swathe of northern Sydney, with four train stations covered by the plan, did not.
The Australian Bureau of Statistics lists Ku-ring-gai as the nation's third most socio-economically advantaged area.
It ranks behind Mosman and Woollahra, which are not included in the policy, and combined have one train station, compared to eight stations in Ku-ring-gai.
None of the other local government areas affected by the policy make the top 10.
Ku-ring-gai councillors voted unanimously in February to reject the proposed changes, citing concerns over infrastructure and heritage properties, among other issues.
But Mr Minns said the area had capacity for extra homes and had a responsibility to do its part.
"We can't be in a situation where the 12 other councils negotiated with the NSW government in good faith to get greater density in their communities and one council says we don't want anything, refuses to meet (and) gets a free pass," he said.
Planning Minister Paul Scully said the area had already benefited from significant transport investment.
"That investment also comes with a responsibility to assist with the housing challenge and confronting the housing crisis," he said.
Ku-ring-gai Council mayor Sam Ngai told AAP he was only offered "one chat" with Mr Scully whom he met in February.
"If I could hop into a car now and talk to him I would.
"Engagement is a two-way conversation ... they've cut things off from their end," Mr Ngai said.
A statement from the council said it would continue campaigning against the policy, seeking infrastructure funding and more consultation.
Opposition planning spokesman Scott Farlow said the government had failed to prove the expansion would be supported by adequate infrastructure.
"For those 37 sites, there is not one dollar which that government has put forward to be able to supply additional school infrastructure, additional transport infrastructure, or additional public open space," he said.
