Mum and dad developers: radical plan to develop your quarter acre block

The NSW government is being asked to “tweak” a rule to allow more townhouses and apartments to be built across Sydney’s suburbs. See where they would go:

EXCLUSIVE: Houses on quarter acre blocks on Sydney’s Northern Beaches, upper North Shore and the Hills Shire could squeeze in thousands of apartments and townhouses under a bold plan to fix the housing supply crisis.

Housing Now – an alliance of big business, unions and academics launched to this week to champion solutions to the city’s housing shortage – wants the Minns government to increase the amount of “building” that is permitted on a standard block of land.

Instead of just a single house, the alliance wants residential blocks to be able to be redeveloped into townhouses or two-storey apartments, as they are in many parts of Paris and London.

The alliance argues changing the planning rule will enable more than 300,000 additional homes to be built over the next five years.

And exclusive analysis of Sydney council areas conducted by CoreLogic for the alliance shows just where these extra homes could go.

Mary Mullins and her kids Henry and Bella just bought a townhouse in North Manly. Picture: Tim Hunter

In recognition that not every site will be redeveloped, the final figures reflect how many extra homes could be created if half the residential blocks were redeveloped.

In Blacktown, the analysis showed the ratio change could lead to more than 21,000 additional apartments and just over 12,000 townhouses being built in the area.

Houses on quarter acre blocks could squeeze in thousands of apartments and townhouses. Picture: NCA NewsWire/Simon Bullard

Up on the Northern Beaches, the change could result in 16,000 new apartments and just over 9000 townhouses.

More than 10,000 apartments could be built in each of Ku-ring-gai, Cumberland, Penrith, Parramatta, Canterbury-Bankstown, Hornsby and Fairfield local governments areas with the density changed, with each area also being able to accommodate another 5000 townhouses.

The change will have less of an effect in already dense areas of Sydney such as Strathfield, with the analysis showing it will receive only 174 units and 100 townhouses.

In order to increase the density, the alliance wants to the government to change the “floor space ratio” rule applying to residential blocks.

In most council areas, the floor space ratio – the amount of building allowed on a site – is about 0.5, meaning a single-storey home covers about half the site. By increasing the ratio to 0.7, the alliance says more dual occupancies, townhouses and two-storey apartments could be built.

As a floor space ratio of 0.7 already applies in North Sydney, Sydney and Woollahra local government areas, there will be no additional housing supply created.

Former Labor housing minister and Housing Now chair David Borger said the change will not only address Sydney’s housing supply issues, but also enable “mums and dads” to build a second property on a single block of land for their kids, or to rent it out.

And should the government take up the alliance’s push for a “pattern book” approach to development, where a predetermined set of townhouses and apartment designs suitable for the area was made available, much of the housing could be fast-tracked, he said.

NSW Premier Chris Minns this week declared he was open to the proposal of pre-approved “pattern book” housing across Sydney.

Mr Minns said he welcomed contributions to the debate about increasing housing supply. Former Liberal planning minister and Faith Housing Alliance chair Rob Stokes backed the proposal.