It’s always been a sort of final chapter of the American dream: Get married and have kids. Buy a house. Move to a bigger house. Downsize to a smaller one.

But a growing number of aging baby boomers are saying, “No, thanks” to downsizing, choosing instead to remain in the same sprawling houses in which they raised kids and created lifelong memories.

“We’re just not seeing that much downsizing,” says Alexandra Lee, a housing data analyst at Trulia, a real estate research firm.

While many older Americans are still stepping down to smaller homes, they're doing so later in life. The trend is contributing to a housing supply shortage across much of the country.

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A more modest home typically means less upkeep and a potential financial windfall as a big chunk of the proceeds from the sale of the larger property can help bolster retirement nest eggs.

Boomers, however, are defying the traditional bounds of advancing age just as they rebelled against the establishment in the 1960s and work- and family-centered values in the 1970s in favor of self-fulfillment.

“They have refused to follow what the traditional expectations were,” says Barbara Risman, a sociology professor at the University of Illinois at Chicago.

There are other forces at work. Boomers, generally those age 54 to 73, are working longer and putting off retirement. Many of their millennial children are living with them well into adulthood. And there’s a dire shortage of less expensive entry-level houses across the country, pushing up prices in that category and making the trade-off less appealing.

Fifty-two percent of boomers say they’ll never move from their current home, according to a Chase bank survey of 753 boomer homeowners released earlier this year. Chase doesn’t have comparable data from an earlier period. An Ipsos/USA TODAY poll of 45- to 65-year-olds in 2017 found 43% anticipated remaining in their current residence through their retirement, possibly indicating the share of non-downsizers is rising.

Many boomers are staying in their longtime homes and communities because they’re deferring retirement. About 20% of Americans 65 and older are working or looking for jobs, up from 12.1% in 1996, Labor Department figures show. Older people are staying in the workforce because they’re healthier and will need bigger nest eggs to finance longer retirements, according to Jennifer Schramm, senior strategic policy adviser for the AARP Public policy Institute. Also, many older workers’ retirement savings were hammered a decade ago, she says.

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Jeff Levy, 58, an insurance broker who lives in a 3,900-square-foot, four-bedroom house in the upscale Memorial section of Houston, plans to work into his 70s. “Our home is less than one mile from my office,” he says. “Downsizing and moving further away from the office is not attractive.”

Levy’s wife, Shelly, 55, wouldn’t mind moving to a high-rise that offers more security and “turnkey” services at some point. “What do we do with this big space?” she says. But Shelly, a legal assistant, adds they would prefer to stay in Memorial and the few condominiums there cost about the same as their house.

Plus, the Levys want to have the house available for visits from their two adult children and, eventually, grandchildren.

“I am looking forward to the day when our children have kids, and they come to our house and play in their parents’ room,” Jeff says.

Staying active

The tendency to age in place is also rooted in boomers’ better health and desire to stay active.

“Baby boomers don’t want to become old in a way that has negative connotations,” Risman says. “Remaining in one’s old house is part of remaining in the prime of one’s life longer.”

Even when they retire, boomers are staying engaged through volunteer work and other activities, says Phyllis Moen, a sociologist at the University of Minnesota.

“They are in the space opening up for the first time in history between the career-and family-building years and the frailties associated with old age,” Moen says.

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Boomers’ penchant to stay in their long-time homes is likely playing a role in low housing supplies, says Danielle Hale, chief economist of realtor.com. The crunch has improved since last year but housing stocks are still well below normal levels.

To be sure, many aging Americans are moving to traditional retirement havens like Florida and Arizona. But even among those who plan to move, 43% want their next home to be the same size as their current one, and 22% want it to be larger, according to a January survey of 50- and 60-year-olds by Del Webb, which builds communities for age 55-plus Americans.

Trulia analysts believe older Americans are simply deferring downsizing. Both in 2005 and 2016, 5.5% of households 65 and over moved, with that share evenly split between those moving to single-family and multifamily homes, according to a Trulia analysis of Census Bureau data. But in 2016, the youngest age at which seniors moving to multifamily homes began to outnumber those moving to single-family houses was older (late 70s) than it was in 2005 (early 70s).

Downsizing, but not yet

Jim Peet, 70, of Plymouth, Minnesota, may seriously consider selling his 3,300-square-foot house but not until he’s 80. Peet, a retired information technology professional, and his wife, Kathee, flirted with downsizing several years ago, largely to reduce maintenance hassles, but found that a condo in downtown Minneapolis would cost more than their house. They also shopped for a similar-sized house in Tallahassee, Florida, but backed out after realizing they didn’t want to be so far from their family.

In fact, their kids and grandchildren generate a consistent hive of activity in their house. “It’s just so comfortable to entertain people,” Peet says. “The kids run from the living room to the kitchen – I love watching them.”

Peet, who uses a walker because of a spine-related injury, also appreciates the support of decades-long neighbors. Recently, he says, a neighbor helped him when he fell from a chair.

Other reasons many boomers are staying where they are:

Millennial kids in the house

Millennials have lived with their boomer parents longer than prior generations as those graduating college between 2008 and 2010, in particular, struggled to launch their careers. In 2016, 16.1% of senior households had younger generations living with them, up from 14.4% in 2005, according to Trulia and Census figures.

Starter home crunch

The housing supply shortage is especially curtailing the inventory of the kind of smaller, less expensive homes that boomers may target, Hale says. That makes it harder to find a compact house and pushes up its price, reducing the net profits of any downsizing. From 2012 to February 2019, the bottom third of homes with the lowest prices appreciated an average 8.03% a year, versus 6.39% for mid-level homes and 5.01% for the most expensive units, according to a Trulia analysis.

Many upgrading, not selling

Now that home prices have more than recovered from a skid in prices, the Chase survey showed nearly nine in 10 boomers are looking to make improvements. As a result, many boomers are focused on upgrades rather than downsizing.

Paid-off mortgages

Many boomers have finally paid off their mortgages and don’t want to start making house payments again.

“Why get into another situation?” says Shelly Levy, whose mortgage will be paid off two years. “We've got a nice house. Now it’s our turn to go on vacation.”