One in five households across the country have at least two empty bedrooms.
Data from last year's Census shows almost 390-thousand homes have two or more spare rooms.
It's estimated there are 250-thousand spare bedrooms in Dublin, and 139-thousand in Cork.
Lecturer in Social Policy at Maynooth University, Rory Hearne, says incentives are needed for homeowners to make their spare rooms available amid the severe accommodation shortage:
"The record levels of homelessness, and then on the other side, look at huge numbers, hundreds of thousands of unoccupied bedrooms."
"There's students out this morning, I know with Student's Unions leafleting, looking for people to see if they can offer digs to students."
"So there is a real issue here that we have a massive number of bedrooms being unused and we need to see can we find ways to use them?"