The House Subcommittee on Financial Institutions yesterday approved a bill to limit the expansion of nonbank banks and edged closer to passage of another bill that would permit interstate banking.

The subcommittee approved by a voice vote a bill that would allow nonbank banks established as of May 9, 1984, to remain in existence but would allow no further expansion of the specialized financial institutions.

Nonbank banks have been used to get around federal restrictions on interstate banking or on who can own a bank.

Federal law defines banks as institutions that both take checking account deposits and make commercial loans. Nonbank banks offer one service or the other, but not both.

Under the leadership of Chairman Fernand J. St Germain (D-R.I.), the legislators beat back attempts in considering the interstate banking bill to limit bank expansion to regional agreements without a guaranteed trigger to full nationwide interstate banking.

They also defeated an attempt on the nonbank bank bill to outlaw all existing nonbank banks and to require their owners to divest them. St Germain had warned that the proposed measure would kill the bill's chance of passage on the floor.

The actions of the 30-member subcommittee are important because they usually foreshadow the vote by the full 49-member House Banking Committee, which is also chaired by St Germain.

By a vote of 16-to-3, the members defeated an amendment by Georgia Democrat Doug Barnard Jr. that would have left the development of regional banking in the hands of state legislatures and also would have provided for a sunset clause -- providing for expiration of the legislation after five years -- without states being required to go to full interstate banking.

Instead, the subcommittee opted for a compromise, opposed by John J. LaFalce (D-N.Y.), that would not require states to participate in interstate banking.

However, if they chose to do so, they would be required to progress to interstate banking after a certain time and could not exclude any states.

In existing regional compacts, New York and California, which have the bulk of money center banks, are most often excluded.

The subcommittee defeated by a vote of 16-to-3 an attempt by Buddy Roemer (D-La.) to eliminate all existing nonbank banks and give their owners two years in which to divest them.

Instead, the subcommittee voted to grandfather, or permit 109 nonbank banks, by setting the cutoff date at May 9, 1984. Last year the banking committee agreed on a cut-off date of July 1, 1983, which would have grandfathered 88 nonbank banks.

St Germain, who argued vehemently last year for the July 1 date, said yesterday that the political facts of life were that the bill would not pass if the earlier date were included.

The committee also dealt with concerns raised by Federal Reserve Chairman Paul Volcker about what he called nonthrift thrifts.

At issue are thrift institutions that are taken over by commercial firms that want to take advantage of federal insurance but usually are interested in using the assets of the thrift for nonhousing purposes.

The subcommittee voted to create a qualified thrift test, meaning that 65 percent of a savings institution's assets must be in housing-related activities for the institution to remain chartered as a savings association.