The Jewish Museum San Francisco has left its longtime site and won't have a permanent exhibition space until it relocates to Yerba Buena Gardens in late 2001 or early 2002.

The move from the Jewish Community Federation building at 121 Steuart St. was strictly a business decision, according to Rabbi Brian Lurie, the museum's president and CEO.

The Jewish Museum San Francisco has occupied the first floor and basement of the JCF building since October 1984. It recently has been paying approximately $5,500 a month in rent.

Lurie said he hoped to retain only the first-floor gallery space. But rent for that space was more than the museum wanted to pay.

With the institution preparing for a major expansion, Lurie said he is trying to raise $65 million to $70 million. "Every nickel I can save toward that is important."

The museum's most recent exhibit closed in late July; the lease ends the last day of this month.

After leaving the Steuart Street space, the museum will continue to mount programs in other locations until its new facility opens. If the JCF doesn't lease both floors to a new tenant, the museum may continue to rent the gallery from time to time as well as take advantage of other temporary sites.

"We are looking for appropriate venues to host what we are calling demonstration projects, pilot projects of the programs being developed for the new institution," said Jennifer Burns Levin, the museum's demonstration project director.

Planned projects include co-sponsoring "Desert Cliché: Israel Now — Local Images," opening Thursday at the Yerba Buena Center for the Arts. The museum also will hold digital storytelling workshops for teens just back from a leadership mission to Israel.

"We're not closing at all; the emphasis is different," Lurie said. "In the next three years, we're going to open a new, very exciting reality. In order to do that, we need to gear up."

That makes sense to Seymour Fromer, executive director emeritus of the Judah L. Magnes Museum in Berkeley. Among museums planning to relocate, "it is standard to devote major energy and thought to the new facility," he said.

Lurie acknowledged some board members fear the Jewish museum may fade from public consciousness if it is no longer open.

The museum CEO said he does not share such concerns, however, as the museum will continue to maintain a presence in the community.

Fromer believes that is an important strategy.

"I think it will be good if the Jewish museum can retain some continuity by having exhibits in various locations in the community," he said.

"I think the audience will look with anticipation to the reopening of the museum," he said. "In the meantime, they'll probably visit other museums."

Behind the scenes, the museum is working to raise funds while it reduces its expenses.

Besides leaving the JCF building, the museum is consolidating its administrative office space from three locations into one. As of this month, the offices have been relocated to 166 Geary St., just below Union Square.

"We need the synergy," that comes from having all staff members in one place, Lurie said. "We can expand in this space. It allows us much greater flexibility."

The Jewish museum eventually will reopen in the historic Jessie Street substation, formerly used by Pacific Gas & Electric Co. but vacant for decades.

Daniel Libeskind, a world-renowned architect who designed the new Jewish Museum in Berlin, was appointed earlier this year as architect of the project.

He will be in charge of renovating the current 16,000-square-foot building and designing a new addition to the north and west. The total space will grow to 70,000 square feet.

Lurie expects the new site to draw at least 275,000 patrons a year, 20 times the number of visitors that the old, much smaller site attracted.

"It's going to be an exciting, dynamic place," he predicted.

Meanwhile, the federation will decide in September what to do with the vacated museum space, said JCF chief operating officer Sam Salkin.

"When the building committee gets itself reorganized," he said, "I'm sure the gallery space will be at the top of their agenda."