Census data shows there could be up to 13 million spare bedrooms across the country.
Homesharing advocates say clearer rules could encourage owners to rent them out.
Homeowner Ali Bradley considers herself one of the lucky ones and would like to pay it forward by renting out some of her spare rooms at an affordable rate.
Ms Bradley said the goal would not be to make money, but to provide housing, and in return, she could continue to afford the maintenance bill for her older home.
Property economist Lyndall Bryant has been researching what she characterises as boarding arrangements for several years.
Dr Bryant said her research had shown there were a few barriers, and chief among them was the fear of taking in a renter or boarder meaning a person was liable to pay both income tax and capital gains tax, as well as the impact it could have on a pension.
People were also concerned about safety and security if they took a stranger into their home, she said.
Dr Bryant said there were overseas examples, including in Ireland, of schemes which incentivised boarders. For example, the government could set a threshold for affordable rent for a room at which a person wasn't taxed.
Federal Home Affairs Minister Tony Burke reignited discussion about these rooms earlier this month in a speech about migration where he remarked on living styles having changed across the years to mean fewer people per household.
Some data, including a 2019 survey of older Australians conducted by the Australian Housing and Urban Research Institute showed only small numbers of people wanted to rent out a room in their home.