What should metro-area counties, cities and towns be aiming for as the challenge of providing senior housing grows more complex with demographic shifts? Options — lots of options.

Older adults are a rapidly growing part of the Twin Cities-area population, according to new Metropolitan Council data. Like their ranks, demand for housing to suit them is projected to soar in the coming decades. And that means the housing stock in the region must adjust.

By 2040, the population of those 65 and older will have more than doubled — from 307,000 in 2010 to 783,000. By that time, nearly one in five Twin Cities residents will be an older adult. More broadly, the latest forecast from the seven-county governmental body also estimates that the metro area will grow by about 783,000 residents, reaching 3.63 million in 25 years.

Living quarters occupied by older adults will make up 33 percent of all households in the region over the next generation, compared with 17 percent in 2010, said Libby Starling, the Met Council's manager for regional policy and research. Starling points out that the boomers — and the Generation Xs and Ys that follow them — are not a one-size-fits-all generation on most things, including how and where they want to live.

It's a trend that developers and young families should heed as well. If the right combination of housing options is available for the 65-plus set, they'll leave larger homes and make them available to younger couples with children. That means communities will want to encourage the development of a mix of housing options that includes rental properties. Surveys indicate that a good number of seniors are no longer interested in owning after they leave their homes.

Some empty-nesters want to leave larger suburban homes for smaller quarters in the cities. Others like the idea of staying in the communities in which they've established roots, but in smaller homes, apartments or condos. Some want to give up driving and be closer to transit. And not all of them yearn to live in a 55-and-older, adults-only environments. Some like mixing in with younger neighbors.

Affordability is also a major factor for seniors. Options to rent, own a smaller space or retrofit an existing home should be available at a variety of price points.

Communities, developers and nonprofits involved in planning and building housing should also be open to new types of housing. Starling says, for example, that one-level homes with two master bedrooms for unrelated adults could appeal to some seniors.

Another way for communities to learn more about elder housing needs is simple: Ask seniors what they want. Some metro-area communities have done just that by hosting meetings with older residents. Guiding smart strategies to meet evolving housing demands will not happen by accident. Metro communities must plan and guide housing changes as demographics change and the marketplace evolves.