Editor's Note: This story was corrected on June 7, 2010, to fix a spelling error.

As Jim Goetz shows off the new addition to his law firm's historic building at Mendenhall Street and Grand Avenue, he hones in on the similarities between the old and new wooden staircases.

The new ornate newel posts, balusters and handrails match those of the 1904 Ketterer Building, which is listed on the National Register of Historic Places.

Goetz said when designing the new south wing, he "didn't want to overshadow" the old building.

And he seems to have succeeded. It is difficult to tell the difference between the two halves.

For that, Goetz credited Intrinsik Architects, Martel Construction and, particularly, his wife, Jill Davenport.

Davenport designed the interior, which includes New York-style black-and-white tiled bathrooms, antique stained-glass windows, wood floors and recycled antique light fixtures. Her scenic paintings also hang throughout the new wing.

One of Davenport's decisions made contractors and some in the law office a little nervous. She wanted the walls of one conference room painted admiralty blue, a hue somewhere between navy and royal blue.

"I said hang in there," she said she told them. "If you don't like it, I'll pay for the repainting."

Turned out, that wasn't necessary.

The two halves of the building, old and new, are separated by a granite-floored and windowed portico and red-bricked patio. Architect Henri Roch Foch, of Intrinsik Architecture, said "it was important that they were physically separated to maintain the historic integrity of the original Ketterer Building."

The team from Intrinsik also added some new space below street level, including a second contemporary-style conference room.

But that space feels nothing like a dark and dreary basement.

A Thursday open house was the first time Roch Foch had seen the room fully appointed, with a large black table, 12 chairs, bookshelves filled with leather-bound legal texts and a huge flat-screen television.

Large windows at one end of the room frame Bozeman artist Zak Zakovi's outdoor sculpture. One of Davenport's large, dramatic paintings hangs on a wall.

Roch Foch stared wide-eyed, taking it all in, and simply said, "That's spectacular."

The installation of his stone-and-metal sculpture, "Tree Thoughts," brought Zakovi's career full circle. The Emil Ketterer building was one of Bozeman's first art galleries back in the 1960s, the sculptor said.

"That noble old building is where I got my start as a craftsman in this town," Zakovi said.

At one point, Goetz considered moving the firm's offices to the Story Mansion on Willson Avenue. He offered to renovate the historic building and leave some of it open for public use. But the Bozeman City Commission opted for a different plan for the historic house.

In the end, it cost the law firm a lot less money and turned out to be more fun to stay in the former blacksmith's home, Goetz said.

"It was both less expensive and allowed us to be more creative," he said.

Story Mansion "would have been an interesting and worthwhile project" but it would have had to been a historic restoration.

Jodi Hausen can be reached at jhausen@dailychronicle.com or 582-2630. Read her blog at jhausen.wordpress.com or follow her on Twitter @bozemancrime.

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