ATLANTA -- Homeownership remains an impossible dream for many low-income families in the Southeast, and a study released this week said it is even more out of reach than previously thought.

The study found that high prices for homes, rising interest rates and debt already carried by low-income families in the region combine to keep them out of the home market.

"This would keep them in a rental market instead of buying their own home," said Richard Fritz, a research officer at the Federal Home Loan Bank of Atlanta who conducted the survey.

"What we're saying is, the lending institution isn't going to grant {low-income families} the loan ... unless they get some kind of supplemental help," Fritz said.

The study concentrated on low-income families, defined as those whose income is 80 percent or less of the local median level, in 32 cities in the District, Alabama, Florida, Georgia, Maryland, North Carolina, South Carolina and Virginia. The study did not compare conditions in the Southeast with those elsewhere.

The researchers used a formula that takes into account the number of low-income families, their ability to buy and the availability of homes priced at 80 percent of an area's median level. On the "affordability index" that the researchers developed a score over 100 indicates that the local housing market is affordable for such families while a level below 100 means the market is not affordable.

Among large metropolitan areas, for example, Norfolk had the most attractive affordability index at 107 in 1989 while Atlanta's was 68. The Washington area had an 83 rating.

Among smaller metro areas, according to the study, the index ranged from Pensacola, Fla., at 136 last year to 85 in Montgomery, Ala.

For the region overall, the index for large metro areas was 93 and for smaller cities 104 in 1989. In 1988 it was 99 for larger cities and 111 for the smaller cities.

According to U.S. Census Bureau figures, about 39 percent of the population in the Southeast are low-income under the definition used in the bank's study, Fritz said.

Though Fritz cautioned against comparing one area against another, Florida tended to have the most affordable home markets for low-income families while the Carolinas had the least affordable.

"Florida consistently had the lowest rates. One reason is it is heavily banked -- it is a very competitive state," Fritz said.

Fritz said that previous studies of home affordability may have underestimated the problem because the groups surveyed also included upper-income families.

A recent study by the National Association of Home Builders, for example, included 28 of used in the new survey. Of those cities, Fritz said, 79 percent were found to be less affordable in the new bank study than in the NHBA study.

The bank's study included only low-income families and assumed that these families had 9.1 percent of their gross income going toward other debts, such as credit cards and car payments, thus limiting their ability to keep up mortgage payments.

The generally accepted debt level for statistical studies is 8 percent, Fritz said, but the bank's interviewers found that to be unrealistic.

"That's like going to the bank and finding the {mortgage} interest rate is a full percentage point higher," Fritz said.

Fritz added that his study assumed that low-income families would make a 5 percent down payment on a home, rather than the 20 percent used in previous studies.

Several institutions, including the Federal Home Loan Bank System, make low-interest loans available for home buyers, but the need is far greater than the money that is available, said Robert S. Warwick, vice president of the Atlanta FHLB.

"It is fair to say that overall the resources available to the low-income for housing is terribly inadequate," Warwick said.