It's only a matter of time before an influx of older people lose their homes and end up on the streets, Alone Ireland has said.
The charity, which supports the elderly to age at home, has launched a campaign to raise awareness of the "hidden housing crisis" among older people.
Alone chief executive Sean Moynihan told the Herald that as people age, they often can no longer afford to pay their rent.
"At the moment, an older person relying on their contributory pension can't afford to rent a home," he said.
"There is an assumption within the pensions system that older people do not need to rent or do not have accommodation costs, yet in 2016, there were 15,883 people over 60 in the private rental sector."
With the number of elderly rough sleepers relatively low, Mr Moynihan fears that the figures will increase dramatically if the Government does not act.
"At the moment, the councils are doing what they can to provide accommodation to elderly people in desperate need, but as numbers of older renters go up, how can they possibly cope?" he said.
Alone is calling on the Government to provide funding toward developing a new, age-friendly model of housing.
It also wants Rebuilding Ireland - a Government scheme that aims to increase the delivery of homes nationwide - to be updated to reflect the needs of an ageing population.
"The housing crisis will only get worse as our population ages," said Mr Moynihan.
"The current generation can't buy homes, but if nothing changes, huge numbers won't be able to afford to rent as they age either. The private rental market is not suitable long-term for older people.
"For most people when they retire, they lose 60pc of their income. The thousands of older people who retire every year in private rented accommodation face a very uncertain future."
In 2016, there were 876,423 people aged 60 or older living in Ireland. By 2031 it is estimated that this will grow to 1.42 million people.
One man who knows first-hand what it's like to struggle with homelessness in later life is Noel Murphy (71).
For 38 years, the Longford native worked as a security guard, but after his marriage broke up, he became homeless.
Speaking to the Herald, Mr Murphy said he went from hostel to hostel at the age of 67.
"It was very difficult and had a big impact on my mental health," he said.
"I was living in a three-bedroom house in Blanchardstown with my family, but due to domestic issues I was plunged into homelessness.
"Every day, I had to ring around many different hostels just to get a room for the night. It was very demoralising."
Mr Murphy was then referred to Alone by Dublin City Council, which has accommodated him at Willie Bermingham Place for the past three years.