DALLAS — Adults in their mid-20s are now more likely to live with a parent than with a spouse.

Married couples and families are increasingly likely to share their home with unrelated housemates.

Couples are increasingly living together without getting married — often with friends, relatives or other roommates under the same roof.

Those types of changes in household composition have big implications for the housing market in Dallas-Fort Worth and nationwide, Igor Popov, chief economist for Apartment List, said in an interview with the Dallas Business Journal.

“It’s become, ‘Let's all create these messy, interesting household types,” Popov said. “(Changing household makeup) creates new demand for different types of housing.”

A large part of the changing dynamics has to do with the rising cost of apartments and homes in cities with job opportunities, Popov said. Other factors, such as high levels of student loan debt, also play a role, he said.

Renters and homebuyers are finding strength in numbers, Popov said.

“One thing happening in lots of metro areas, especially in cities with lots of growth like Dallas, is a lot of households are banding together, meaning bigger households,” he said. “It’s a very popular survival strategy.”

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Fifty years ago, 76 percent of 26-year-olds in America lived with their spouse, according to an Apartment List report released Oct. 1. Today, that share has plummeted to 24 percent. In fact, 26-year-olds are now more likely to live with a parent than with a spouse, according to the report, which used data from the U.S. Census Bureau.

That means 20-somethings who in the past would be renting apartments or buying their first house aren’t making the move because they’re living with their parents, Popov said.

The trend toward more diverse household types has implications for apartment and single-family home developers and builders, for researchers, for property marketing agents and others, he said.

Popov sees room for improvement.

“I don’t see marketing strategies that try to emotionally resonate with people living with mom and dad into their late 20s, but that is a big demographic,” he said. “People underestimate how much of a group of potential consumers there is in the rental market that are living with their parents.”

In Dallas-Fort Worth, the number of households in which families live with roommates — either related or not — jumped from 50,508 in 2007 to 67,630 in 2018, an increase of 33 percent, according to the report. Nationwide, families with roommates rose 14 percent in the same period, from 2,095,421 to 2,396,567 households.

Unrelated households, defined as multi-person households in which at least one member is not related to the others, increased sharply in DFW, too. There were 102,694 in 2007, the year before the housing market bubble burst, and 128,511 in 2018, for an increase of 25 percent.

Nationwide, the number of unrelated households rose 21 percent, from roughly 4.5 million in 2007 to about 5.5 million in 2018.

For apartment developers, homebuilders and others in the housing business, trends in who lives together are determining what types of housing will ultimately be available and affordable, Popov said.

“I think we’re going to start seeing more construction geared toward having a place for a roommate with maybe a second entrance or maybe a guest house in the back for the roommate that’s helping the family afford their rent or their mortgage,” he said.

Looking ahead, even if the housing industry adjusts, Popov said he expects rents and mortgages to continue to rise, making roommates and nontraditional co-living arrangements even more common.

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