Efforts to shore up confidence in Fannie Mae and Freddie Mac following a Sept. 7 federal takeover have sparked uncertainty among some observers about the mortgage giants’ future role, not only in single-family housing but also in the multifamily sector.

Jerry Howard, National Association of Home Builders executive vice president and CEO, calls the federal action “unfortunate” but says homebuilders are hopeful that it “will help to increase liquidity in the nation’s mortgage markets and restore confidence in the global financial markets.”

Fannie and Freddie hold about $5 trillion in mortgages, nearly all of which are for single-family homes. But they also have emerged as increasingly critical factors in the multifamily residential market, says Doug Bibby, president of the National Multi Housing Council. Together, Fannie and Freddie had $170 billion in their multifamily mortgage portfolios as of June 30, and are, “for all intents and purposes, the market now,” Bibby says.

Bibby says the government’s rescue plan emphasizes securitizing residential assets, a mechanism used commonly in singlefamily homes. However, he is uncertain what plans will be for the portfolio vehicles used typically in multifamily financing. “We’re concerned the multifamily market could be disadvantaged [in] its ability to do portfolio executions,” Bibby says.

Lawmakers echoed concerns about the two organizations’ uncertain future. Senate Banking, Housing, and Urban Affairs Committee Chairman Chris Dodd (DConn.) said he would call the plan’s architects before his panel for answers. “There are still many unanswered questions about the administration’s plan, and Americans deserve to know if this unprecedented proposal will help keep mortgages affordable, stabilize the markets and protect taxpayer interests,” says Dodd.

Lawrence J. White, an economics professor at New York University’s Leonard N. Stern School of Business, says the move was “probably inevitable.” White, who served on the Federal Home Loan Bank Board in the 1980s, expects that in the long run the takeover will help both the economy and consumers.