A $21 million project to restore Hawaiian Hall at Bishop Museum is at the halfway mark, and preservationists now will begin the tedious work of readying exhibit cases for delicate artifacts.

At a preview yesterday for work conducted so far, officials said preservationists have varnished interior koa in the building and restored bronze columns long ago hidden under plaster. Contractors also have put in an elevator, allowing people with disabilities to see the upper floors.

The hall was never outfitted with an elevator, which meant the elderly, those in wheelchairs or others who have difficulty climbing stairs were unable to see many exhibits, said museum interim President Michael Chinaka. The elevator also will service adjacent Polynesia Hall, which is now connected to Hawaiian Hall with a courtyard.

The Hawaiian Hall renovation kicked off in June 2006 and is expected to take about two years to complete.

Standing in Hawaiian Hall yesterday, Chinaka said the biggest headaches with the renovation have been unexpected ones.

"When you do a renovation, you never know what's behind the walls," Chinaka said, with a laugh. "This started out as a smaller project."

But shortly after work started, he said, contractors discovered unforeseen wood rot, termite damage and structural support problems.

As a result, the price tag of the renovation grew by about $1 million.

The restoration of the hall is by far the largest project the museum has ever undertaken and is the first major renovation for the building.

Chinaka said the main goal of the project is to restore the building to about what it looked like in the 1940s, but with a modern twist.

In addition to shellacking its koa interior, contractors are restoring flooring, stairways, roofing, windows and architectural detail work.

The modern aspect of the renovation will be incorporated into the building in two ways: first, with modern conveniences, such as reliable air conditioning, new lighting and techniques to preserve artifacts, and second, with interactive, state-of-the-art exhibits.

The exhibits could include computer touch screens or other innovations. The rare koa exhibit cases, built into Hawaiian Hall, will be refurbished to house fragile feather capes and other Native Hawaiian artifacts in temperature-controlled, dust-free atmospheres.

Just about the only exhibit that will stay the same will be the 50-foot-long whale hanging from the ceiling of the hall. The specimen is encased in plastic for protection during renovation work.

Once the renovation is finished, groups and individuals that chipped in to help the project will get a sneak peek at the finished product.

Museum officials are planning a big grand opening bash for the general public, too. Families will likely get in free to see the new hall.

"For Bishop Museum, it (the renovation) is monumental," said Allison Holt Gendreau, co-chair of the Hawaiian Hall capital campaign committee. "It's the oldest monument on our property."

The renovation is being overseen by Ralph Appelbaum Associates of New York, a museum planning and design firm that won accolades for its work on the United States Holocaust Memorial Museum.

While the renovation is moving forward, officials are still trying to raise more money to finish the project. So far, the Kalihi institution has garnered about $13.5 million from various public and private sources, including $75,000 from the Bank of Hawai'i Charitable Foundation, which was handed over to the museum in a ceremony yesterday.

Groups have pledged an additional $3.5 million, and the museum is still looking for about $4 million to complete the renovation.

Reach Mary Vorsino at mvorsino@honoluluadvertiser.com.