The housing market may not be able to rely upon immigrants to help save its bubble from bursting -- should it come to that -- because many immigrants can't afford to buy a home and they live in crowded conditions to make ends meet more often than native-born Americans.

Studies that say housing bubble bursting theories overlook demand from immigrant home buyers may be overlooking the fact that immigrant working families are nearly 70 percent more likely than native-born Americans to spend more than half their income on housing.

Immigrant working families are also six times more likely to live in crowded conditions than native born Americans, indicating many can't afford to buy, according to "America's Newest Working Families: Cost, Crowding and Conditions for Immigrants," by the National Housing Conference's (NHC) research affiliate, the Center for Housing Policy.

The Washington, D.C.-based, non-profit NHC develops resources and policies to increase the availability of affordable housing. The report defines working families as low- to moderate-income families working the equivalent of a full-time job and earn between the full-time minimum wage of $10,712 and up to 120 percent of the median income in their area.

The Center for Labor Market Studies at Northeastern University found recent immigrants were critical to the nation's economic growth in the past decade, accounting for half of the new wage earners who joined the labor force in those years. That same study also cited evidence that most immigrants contribute more in taxes than they use in services.

They may not, however, be as powerful a housing market force as previously considered.

"As the fastest growing segment of America's workforce, immigrants are of increasing economic importance to their communities, but affordable housing concerns and crowding data revealed in this study make it clear that today's immigrants are facing more than the traditional challenges of their predecessors," said NHC Chairman G. Allan Kingston.

The nation's largest minority, Hispanics, comprise almost 60 percent of immigrant working families with critical housing needs, they spend more than half their income on housing, and, or they live in severely dilapidated conditions, the report said.

Asian immigrants account for another 20 percent of those with critical housing needs. Others include families from Europe, Canada, Africa and the Middle East.

Also, immigrant working families live in crowded conditions (more than one person per bedroom) more often than native-borns, 15 percent versus 2 percent and there are greater numbers of immigrants living in crowded conditions -- 1 million compared to 840,000 native-borns.

One in five immigrant working families who rent are crowded, while just over one in 10 immigrant families who own are crowded. Both are rates considerably higher than those for native-born working families.

Crowding is more pronounced in some regions, with the West and Midwest revealing the most crowding. Not just a city problem, critical housing needs among immigrant working families hit 45 percent of the time in the suburbs and 50 percent of the time in the city.

While some studies show immigrants are ready to buy a home five years after they arrive, the NHC study found that not only recent immigrant arrivals experience housing problems, but of the low- to moderate-income immigrant working families with critical housing needs, more than one-third of them arrived in the United States between 1980 and 1989.

"Immigrant working families are significantly more likely than their native-born counterparts to spend over half their income on housing, while immigrants are also more likely to live in crowded conditions," Kingston said.