WASHINGTON – Owners of shopping malls, hotels and offices are defaulting on their loans at an alarming rate, and the commercial real estate market is not expected to hit bottom for three more years, industry experts warned Thursday.

“The commercial real estate time bomb is ticking,” said Rep. Carolyn Maloney, D-N.Y., who heads the congressional Joint Economic Committee.

Delinquency rates on commercial loans have doubled in the past year to 7 percent as more companies downsize and retailers close their doors, according to the Federal Reserve. Small and regional banks face the greatest risk of severe losses from commercial real estate loans.

The commercial real estate market’s fortunes are tied closely to the economy, especially unemployment, which hit 9.5 percent in June.

Funding for commercial loans virtually shut down last year as the financial system unraveled. Industry executives say financing is still extremely difficult to obtain, even for financially healthy properties.

Losses in securities backed by commercial property loans could be as high as $90 billion in the coming years, said Deutsche Bank analyst Richard Parkus. He said even more losses – up to $140 billion – are expected from construction loans made by regional and local banks, rather than those sold as securities held by investors.

“We believe the bottom is several years away,” Parkus told lawmakers.

Industry groups are pushing for the government to launch government programs to support commercial real estate loans.