Gloom was the watchword at the recent housing and economic outlook seminar of the Federal National Mortgage Association.

Among the predictions:

There will be a slow recovery from the recession.

Housing starts will remain low.

Mortgage rates will remain high, although price increases will moderate.

For some time the housing industry has been betting that demographics would make the outlook for the 1980s bright, with the maturing baby-boom generation requiring up to 2.5 million units of housing annually.

But Kenneth Rosen, chairman of the Center for Real Estate and Urban Economics at the University of California at Berkeley, cautioned against relying on that theory.

"Households don't form just because people are there -- it depends on the state of the recovery from the recession," he said. During the slow recovery ahead, many new renters or buyers will double up with others rather than striking out on their own, he predicted.

Calling himself "cautiously pessimistic," he said there may be starts on 1.4 million new housing units next year, instead of the 1.9 million demographics would seem to demand.

Michael Summichrast, chief economist of the National Association of Home Builders, predicted little acceleration in house prices before 1982.

Lawrence Chimerine, chairman of Chase Econometrics, said he believes the housing recovery will be half as rapid as the decline, with starts not reaching 1.75 million until 1982. Mortgages rates during the next several years should hover between 12 1/2 and 13 percent range, he said.