Laura Cina doesn't want a roommate. She would prefer to share her beige, ranch-style house in Minneapolis with only her 17-year-old son. And after having a roommate over the summer, one who also was a close friend, Cina, 35, decided that she would see if she could make the finances work without renting out a room.

But after a couple of months, she realized that her salary as a managing director for a renewable-energy organization just didn't cover the bills. So in March she posted an advertisement on Craigslist looking for a roommate who can get along with her two fat bulldogs. She's had a couple of bites, but the only person who wanted to move in couldn't provide a security deposit.

"Right now, I'm looking for a woman -- unless I get desperate," Cina said. "I would love to have a friend take the room, but I don't have that option now."

Cina is one of a growing group of Americans in their 30s who are turning to roommates to help cover their living expenses in a poor economy. From 2009 to 2010 the number of thirty-somethings living with nonfamily roommates rose from 10.6 million to 12 million, an increase of 13 percent, according to data collected by the Census Bureau and the Department of Labor.

Experts say that several factors are behind the increase, including high unemployment brought on by the recession, stagnant wages for many workers and escalating housing prices. The net effect is that in 2010, 2.6 million more Americans were living with roommates than were in 2006, according to Census Bureau data. Most of that growth occurred in the over-30 set.

"It used to be only college kids did it, but people are increasingly finding that the only way to live is with roommates," said Frances Goldscheider, an expert on housing arrangements and a professor at the University of Maryland in College Park. "I don't think that it means that we're getting along any better, or that we like each other any more. It's a response to the current squeeze."

Cina lived with roommates when she was in her 20s, but never expected to be sharing a house again.

Neither did Jeff Gunther, 46, who is looking for a roommate to share his home outside Denver.

"It's kind of tough to come to the realization that you have to live with somebody," he admitted. "You're used to living alone and having a stranger in your house is, I'm sure, going to be uncomfortable at first."

Many economists see the rise in roommates as having a significant impact on the greater economy. Nonfamily roommate arrangements compounded with more adults moving in with their parents have resulted in an estimated 2.1 million fewer new households, according to a study by the National Association of Home Builders.

And those potential households have real monetary value.

"Every additional housing unit would represent $100,000 in terms of construction costs, so clearly it's having an impact on the economy," said Michael Carliner, a housing economist and fellow at the Harvard University Joint Center for Housing Studies. "In this cycle, it has been holding the economy back."

While the downturn triggered by the bursting of the housing bubble pushed more people to share housing, an economic recovery should have the opposite effect because there is pent-up demand from people tired of sharing quarters.

But experts such as Carliner point out that there is something of a chicken-and-egg scenario behind such projections. The economy needs to improve to encourage roommates to move into their own homes, yet the economy might not improve as quickly until they have moved out.

"The longer it stays pent up, the longer it is before we have a full recovery," Carliner said.

But apart from the financial motive for seeking a roommate, many people point to an additional reason to invite a stranger into their homes: companionship.

"I've been so lonesome, I want someone in here," admitted Euan McCreath, 38, who recently broke up with his girlfriend with whom he was sharing an apartment in Bridgeport, Conn.

Gunther, of Westminster, Colo., agreed.

"I have to admit that I've become a little bit of a shut-in, so I am looking forward to having somebody else there, somebody to socialize with," he said.

But even then Gunther sees sharing his home as only temporary.

"I've accumulated some debt, so once I get that paid off, that would be it," he said. "No more than a year."