Sydney could be facing a housing shortfall to the tune of 80,000 homes by 2014, says the Urban Taskforce.

Commenting on the New South Wales’ “plummeting” rate of building approvals, Urban Taskforce chief executive Aaron Gadiel estimated that Sydney’s current housing undersupply has reached 46,000 homes – up from 36,000 in 2009.

"New South Wales' private sector home approval rate is plummeting at more than three times the national rate,” said Gadiel.

"We've now seen three straight months of data, where the NSW private sector home approvals have trended down by more than 4% a month,” he added. "Since March, that's added up to a 12.6% decline in new private sector home approvals.”

New South Wales’ figures are especially of concern when compared to those of other states, noted Gadiel.

Over the same three-month period, the decline in new private sector home approvals in Victoria was less than half of New South Wales’ figure at 5.6%, while Western Australia’s decline was 3.2% for example.