When the stained-glass windows at Congregation Sherith Israel in San Francisco were reinstalled last week, it was a certifiable goosebumps moment.

“Oh my God, my heart stood still,” said Lynn Sedway, president of the congregation’s board of trustees. “To watch the [five] prophet windows and the rose window go in was one of the greatest events of my life.”

The reinstallation of the windows was a major milestone in phase one of Sherith Israel’s renovation project, which began last April. Another visible sign of progress is the return of the sanctuary building to its original Colusa sandstone exterior.

The sanctuary is on target, Sedway said, for what should be an exhilarating, communitywide, late-March grand reopening — but all of the activity on Jan. 24 and 25 was pretty exciting, too.

“We have been working so hard on this, and now we’re starting to see the results,” a beaming Sedway said. “As the scaffolding has started to come down, you can begin to see the building as it was initially designed. And not only are we preserving this incredible, historic building, but we are also preserving this vibrant community — and I am truly overcome by the emotion of it all.”

Tom Lehnartz (on ladder) shows the rose window to Art Femenella (left), who was in charge of the stained-glass restoration, and Raphael. The window is 16 feet across and weighs 1,000 pounds.

With the windows back in place and the interior strengthening work on target, the major portion of the retrofit is about 85 percent complete, according to Craig Etlin, congregational vice president and chair of the building and grounds.

Other good news arrived recently in the form of two big donations: $200,000 from the Koret Foundation and $50,000 from the Bernard Osher Jewish Philanthropies Foundation.

The grants pushed the total raised for the project to $6.3 million, nearly 80 percent of the $8 million fundraising target for phase one. The second phase will begin once the congregation can raise an additional $4 million.

The retrofit was necessary because the temple’s building, including its 373-foot, iconic gold-domed sanctuary, had been in violation of seismic regulations for around two decades. San Francisco approved strict codes for unreinforced masonry buildings after the 1989 Loma Prieta earthquake.

The windows reinstalled last week spent about eight months being restored in a workshop in Milton, Iowa. After gathering dust and muck in the 105 years since the sanctuary opened in 1905, they needed a decent amount of sprucing up.

Each prophet window is 3 feet by 7 feet and weighs 150 pounds. The rose window, featuring 12 teardrop-shaped panels circling a Jewish star, is 16 feet across and weighs 1,000 pounds — but it is not plated like most stained-glass windows, making the restoration that much more difficult.

As far as Rabbi Larry Raphael is concerned, the most difficult part of the project was simply getting started.

Rabbi Larry Raphael (above) of Congregation Sherith Israel shows off the newly restored and installed prophet windows.

“Our tradition has many ways of expressing the idea that beginnings are difficult,” said Sherith Israel’s senior rabbi. “We’ve done the difficult thing, which was to get started. Now, with great hopes and great pride in what our community has accomplished, we look forward to worshipping in our beautiful sanctuary for the next century beyond.”

During construction, services have been held in the synagogue’s Newman Hall and chapel. High Holy Day services were at Calvary Presbyterian Church.

Work that remains to be completed in the first phase includes some core drilling to strengthen the building, work on the beam atop the walls, and repairing and repainting the wooden frames of all the windows.

But for now, people associated with the project are simply taking a huge breath and reveling in the beauty of the windows.

“The stained glass and the colors are so bright and beautifully restored, I hope everyone will come to see them,” Sedway said. “They now have a clarity and a translucence that is hard to describe.”