"We have to do it [ensure more affordable housing for the elderly], we have to acknowledge that it is a growing issue and that we need to provide for it earlier and plan.
"On the whole there has been a trend in New Zealand in the past for older people to own their own homes, or have a bigger house and sell down and relieve themselves of any mortgage.
"The vulnerable ones are the ones who don't have accommodation that they own, they are prey to the vagaries of the rental market, and they perhaps don't have family members who can support them."
Changes to social housing would increase the supply of one or two-bedroom properties, suitable for vulnerable senior citizens, Ms Barry said.
How to prepare for an ageing population is of increasing concern.
New Zealanders aged 65 and over will increase from 670,000 now to 1.4 million in 2055, with those 80 and older going from 160,000 to 614,000.
The 2014 Report on the Positive Ageing Strategy, from the Office for Senior Citizens, tracks progress against "positive ageing" goals and was released yesterday.
It found that a high rate of home ownership among those older than 65 had led to a low 3 per cent hardship rate, despite many on low incomes.
However, people approaching retirement (particularly some people aged 45-64) could be at risk of greater hardship because of falling home ownership rates and high current hardship levels.
Rising council rates and insurance costs were also flagged.
"Some of this is new because we have never before lived for so long, and we never before have had so many people living to this age. We haven't actually had to think of some of these things before," said Robyn Scott, chief executive of Age Concern.
"We already know that for an older person who is renting in somewhere like Auckland, there will be significant financial pressures and challenges for them."
Ms Barry said work would also be done with local authorities on affordable housing for the elderly.
Labour's Housing spokesperson Phil Twyford said much greater urgency was needed on what was a "demographic timebomb that could make the housing crisis much, much worse".
"It now takes, on average, 50 years to pay-off a median Auckland house...we are already seeing a huge wave of retiring baby boomers who don't own their own home."