The days of grandma, parents and their children all living in one house is often a concept many look back upon with nostalgia as a simpler time.

But today, many families are sharing a home not out of tradition, but out of financial necessity.

The number of shared households — those that include at least one resident adult who is neither a student, a spouse or a cohabiting partner of the householder — has jumped nationwide since 2007, when the severe recession began.

New Jersey, meanwhile, has an even higher percentage of such households than the nation at large — and the fourth-highest percentage among all states.

Nearly 18 percent of all U.S. households, 19.8 million, were considered shared households in 2007, according to the U.S. Census Bureau’s American Community Survey.

By 2010, that number had risen to more than 19 percent, or 22.2 million, before dropping slightly in 2011 to 22 million.

In New Jersey, more than 22 percent of households were shared in 2011 — more than 705,000 of them. Only California, New York and Hawaii ranked higher by percentage.

So that means more young adult children living with their parents and more elderly people living with their children, and the result is often a crowded home.

“I live with my grandma, my mother and two sisters,” said Tom Paul, 22, of Brigantine. “My parents have always lived with my grandma — though (now) my grandma lives with us.”

Paul at least lives in a comfortable, three-story home — though recently, there have been fewer and fewer of those and more single-family homes, as well as fewer rental units.

“It’s all those ‘home-rule’ issues,” said Richard Perniciaro, dean of facilities, planning and research at Atlantic Cape Community College. “(Towns) don’t want to pay for schoolkids and new schools. And there are very few multifamily homes being built – so people are crowding more into single-family homes as well.”

As a result, “rents have gone way up,” he said. In New Jersey, and South Jersey in particular, “the rental market is crazy.”

Richard Shaffer III, broker-owner of Resorts Ltd. Real Estate Brokers in Egg Harbor Township, said the rental housing market is strong and occupancy rates are high.

“Typically we have no problems renting out properties,” said Shaffer, whose agency handles condominium unit rentals at many developments throughout Atlantic County.

Still, he said, he’s surprised there isn’t more excess demand for rentals, considering the number of foreclosures and short sales of single-family houses.

Affordable housing in the area mainly means affordable condo units from one to three bedrooms, and there aren’t enough of them to meet demand. Shaffer said such units at the three sections of London Court and the Heathercroft development in the township “turn over very quickly.”

Single-family homes are more available, he said, even though many owners who could be renting them while waiting for the housing market to rebound are not.

But those are sometimes more house than renters are seeking, or more house than they can afford.

“What you will find is that the qualifications for renting are similar to those for buying, as far as income is concerned,” said Shaffer, former president of the Atlantic City & County Board of Realtors.

The Census Bureau said there are definite economic reasons for the increase in shared households.

“Many of the adults sharing a household with relatives would have been in poverty if they had been living on their own,” it reports — but according to how poverty rates are determined, living as a member of the “subfamily” of a householder means that you are compared to the poverty threshold for families of the same size, not as a single person.

So while the householder’s personal income is compared with the poverty threshold for a single person ($11,170 in 2012), or the householder’s and their spouse/partner’s income are compared with the threshold for two people ($15,130), groups of people making up a family have thresholds that may be easier to reach than if the individual members were single.

Many cultures, though, have a history of multigeneration households.

“Traditionally, there was more of a nuclear family in the Latino community, with grandparents living at home,” Atlantic County Hispanic Alliance President Bert Lopez said.

But while younger Hispanics are also living at home more, Lopez said that’s less culture than the same story of economics.

“The majority of younger Latinos have had to face the same dilemmas that other Americans have faced,” Lopez said.

While the number of shared households may have dropped slightly from 2010 to 2011, that may not mean the problems that caused people to live together in one house have receded, he said.

“I haven’t seen that happen just yet,” Lopez said. “Particularly with the slowdown in the casino industry locally. We’re not seeing the benefits of a turnaround just yet.”

Staff writer Anjalee Khemlani contributed to this report.

Contact Steven Lemongello:

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