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Longer lives and medical woes are taking their toll on the older folks, with many needing the assistance of wheelchair ramps, bars or specialized bathroom fixtures to provide safety and comfort.

Even active seniors well able to get around on their own may lack the financial resources to continue living independently, which makes a move into Junior's house a sensible thing to do — as long as they don't kill each other from living in such close quarters.

Grandparents who move in to a son's or daughter's household might not only be doing themselves a favor, but also doing one for their children, by helping out with expenses.

Also, parent who can't afford long-term care insurance, healthcare or assistance in their daily activities avoid the need for a Medicare spend-down and entry into a nursing home.

In terms of home improvements, both health-related and space-related projects are on the rise, according to Kermit Baker, AIA's chief economist.

Households are "adding more space and features to their homes," Baker said in a recent report. "Special-function rooms, which often disappeared from homes during the downturn … are now reappearing.

"Likewise, special home features that were often eliminated during the housing downturn are now increasingly returning to home designs. Home automation features, as well as products that promote sustainability, are also showing up with increasing frequency in both new and remodeled homes." 

What's interesting is the trend toward "aging-in-place" improvements — not just among those who already need them, but among those who are making space in their homes for older parents or other relatives. 

"As many households become caretakers for aging relatives," Baker said, "separate living suites have become popular options for accommodations. Homeowners want to ensure that their homes can support the needs of aging parents who may be staying for an extended period of time and other visitors with accessibility needs." 

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Indeed, dedicated guest rooms, such as au pair/in-law suites, have become very popular.

In 2012, 10 percent of architectural firms surveyed reported seeing more demand for them; in 2013, that rose to 26 percent, and in 2014 to 39 percent.

Also increasingly popular are modifications to accommodate multiple generations in the same house (in 2012 demand had not changed, but in 2013, 50 percent of firms reported more demand, and in 2014, 53 percent said it was increasingly popular).

Other popular features seeing a resurgence are outdoor living rooms — which may seem like a luxury unless you suddenly have multiple generations living in the same house — and home offices.

The latter not only offers a way for a caregiving child to continue working at home while seeing to an elderly parent's needs, but also, according to AARP spokeswoman Nancy Thompson, allow a healthy senior to continue to work past retirement.

Thompson said that the home office is a trend in designated senior housing as well.

The bottom line? The multigenerational household may conjure up visions of the early parts of the last century, when it was more common for grandparents, parents and children all to live together. But with so many people having trouble saving for retirement or paying for healthcare, those days may be returning.

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