And government funding will need to be as much as $290 billion in that period if the shortage is to be addressed, a parliamentary committee investigating housing affordability has heard.

Referencing a National Housing Finance and Investment Corporation independent review, Community Housing Industry Association chief executive Wendy Hayhurst noted 30,000 new affordable units would be needed each year for the next two decades, but just 3000 units per year had been built in the last three years.

The NHFIC review found a $290 billion investment would be required across the next 20 years to address the shortfall, a figure that would not be reached even if funding was increased ten-fold.

Australian Housing and Urban Research Institute research referenced in the review argued an additional 727,300 social housing dwellings would be required by 2036, but Australia's stock had grown by just 29,000 in the 13 years to 2019.

Ms Hayhurst's organisation said a 10-year national housing strategy across all levels of government would be key, but called on the federal government to exercise its "fiscal firepower to do much more".

"A secure and affordable home is a fundamental part of a well-functioning housing system - it's not simply a safety net device for the most disadvantaged," she said.

"It provides individuals who cannot afford to buy a home a foreseeable future with safety and security, enabling (them) not to just get by, but to get on."

PowerHousing Australia chair Nicola Lemon also cited the need to replenish old stock in social housing, with eight million "past their use-by date" homes contributing up to 18 per cent of Australia's greenhouse gas emissions.

SGCH chief executive Scott Langford noted 43 per cent of low-income households were in housing stress.

He said supply formed part of both the challenge and solution, with renters of affordable dwellings requiring to pay less than market value.

He said "targeted supply" would prove key to addressing the crisis, adding: "There's no evidence... simply adding general supply would reduce rent sufficiently to meet the need for affordable housing without further intervention."

Committee member Liberal MP James Stevens agreed targeting an increase in supply specifically to those in need of affordable housing was vital.

"Supply is the issue, but you can't oversimplify it and say 'Just release another million blocks of land'. You've got to do it in a nuanced way and make sure people that need it can get access to it," he said.

Australian Associated Press