The new American household: 3 generations, 1 roof

The Moura family has found that living together helps ease the pain of the recession.

NEW YORK (CNNMoney) -- As the economy continues to take a toll on consumers' finances, a growing number of people are discovering that becoming roommates with mom and dad, or a 20- or 30-something son or daughter, helps to ease some of the financial pain in tough times.

As of 2010, 4.4 million U.S. homes held three generations or more under one roof, a 15% increase from 3.8 million households two years earlier, according to the latest data available from the Census Bureau.

When Alicia Moura's father-in-law, Aecio D'Silva, retired from teaching at the University of Arizona in 2010 to pursue private-sector projects in aqua-culture and bio-fuel, he didn't expect to wait long before his efforts paid off. But then the economy tanked, development funds dried up and his ventures languished.

Soon afterward, Alicia started experiencing some medical issues with her pregnancy and the family decided it would be best to move in together. Now everyone -- Alicia, her husband, their two young daughters and the in-laws -- live under one roof.

"We not only save money by having a joined household, but we save on stress, time and other resources by having in-home day care," said Moura.

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For multi-generational households, there is typically a nice payoff. Not only do they save money, but they are better able to avoid financial hardship.

The Pew Research Center reported that the poverty rate among those who live in multi-generational homes was 11.5% in 2009 (the most recent data available), compared to 14.6% for those who didn't live with other adults other than their spouse or partner.

"It's such an advantage to have multiple wage earners in the same household when the economy is still struggling." said Nicolas Retsinas, a lecturer at the Harvard Business School and one-time head of Harvard's Joint Center for Housing Studies. Retsinas said the multi-generational housing trend is one he expects will continue.

Freeing up finances. Leslie Bos, a mother of three who lives in Boston, asked her mother to move in with her when her mom had to leave her job as a social worker and go on disability due to health problems.

While Bos helped her mother out of a jam -- her disability payments couldn't even cover housing costs in Boston pricey real estate market -- it has also saved Bos significantly over the years.

"The 10-year-olds still need minding after school so this has really cut my child care expenses," said Bos, who works for a company that manages multi-family housing assets.

Census reported that "doubled up households," those including at least one extra adult who is not enrolled in school and isn't a spouse or partner, grew 10.7% to 21.8 million households in spring 2011, up from 19.7 million households four years earlier.

Many of those homes included adult children who flew back to the nest after being unable to find work. The number of 25- to 34-year olds living with their folks jumped by more than 25% between 2007 and 2001, Census reported.

Debby Bitticks' adult daughter, Sandi Krul, moved back in so she could take a break from work and return to law school. Along with Sandi, came her husband and two young daughters. The entire clan live in the Bitticks' Encino, Calif., home with Debby and her husband.

By combining the families, they are saving thousands of dollars a month in duplicate costs, giving Krul the opportunity to change the direction of her career without putting too much financial strain on her family.

Builders take note. "The recession caused doubling up to save money -- and the story is still unfolding," said Steve Melman, Director of Economic Services for the National Association of Home Builders.

The long-term impact, he said, is that more families will want bigger homes with more bedrooms to accommodate their extended families.

In fact, so many relatives are already moving in with one another that builders are starting to construct homes to accommodate them. Instead of offering a two-car garage, for instance, builders will design the house with a one-car garage and use the extra space for a guest room, explained Valerie Dolenga, a spokeswoman for Pulte Homes (PHM, Fortune 500).

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Home builder Toll Brothers (TOL) has started incorporating multi-generational living arrangements directly into its designs -- such as a guest suite with a kitchenette where a family room once may have been, according to Timothy Gehman, the company's director of design. Previously, such accommodations were offered only as custom options.

When Rajendra Hariprashad, moved from Guyana to New York as a boy, he and his mom moved in with his grandparents. Now 34, Hariprashad lives in a four-bedroom home in Glen Oaks, N.Y., with his wife, 10-month-old son, parents, and his sister and brother-in-law and their two-year-old son.

All of the adults in the house are employed, making it easier to afford the four-bedroom, three-bath house, which cost about $600,000.

"But it's more than a financial thing," said Hariprashad. "Everyone thinks we should all have our own homes, but we're so happy living together."

Hariprashad said he envisions his family always staying together, even as the younger generation expands. "We'll just need to buy a bigger house," he said.