BANGOR — The body might look unchanged, but the guts of Norumbega Hall are nearing the final touches, its developer said Sunday.

The project, located across from City Hall on Harlow Street, has been the site of nearly constant construction for more than two years. Robert Duerr, a former Gouldsboro resident now living in Hawaii, hopes that the formerly vacant buildings will spark a revitalization of Bangor’s struggling downtown.

If the final version matches Duerr’s mental bluebrint, Norumbega Hall will include shops and cafes, art galleries, a music hall and office space.

One of the more innovative parts of the project, he said during a telephone interview from his Hilo home, is the heating system for the ballroom. More than 10,000 feet of tubing now snakes across the floor, a hot-water system that will soon be covered with concrete.

In its heyday during the 1930s, the ballroom was part of The Chateau, where big band music bounced off the art deco walls. The Morse building, as it is known, later became home to Sears, which moved to the Bangor Mall about 15 years ago.

Another major part of the project — linking the Morse Building with the Central Block around the corner — also is complete, Duerr said.

Inside, steel studding has been erected, the bathrooms are done, the elevators are nearly ready, and new stairwells are just about there. Adding to the cost and complexity of the project are designs mandated by the Americans with Disabilities Act, which will make the building handicap-accessible.

“The ADA requirements are a big part of what’s going on there now,” Duerr said.

Although a brick sidewalk and some lampposts were recently installed, Duerr said most of the outside work will wait until spring, when he has scheduled a tentative date for opening.

Until then, Duerr will continue his push to lure tenants — including a major business to anchor the complex — to complement what he hopes will be the city’s cultural center. While not yet complete, Duerr said he’s already been asked to rent out the ballroom for weddings and holiday events.

Since he started the project a few years ago, Duerr has seen deadlines pushed back and costs pushed up. Still, when people complain that Norumbega isn’t open yet, Duerr replies that “history wasn’t built in a day.”

“The positive is, the light’s at the end of the tunnel,” he said.