You don't have to be a structural engineer to know that if there's a chimney going through the second and third floors of a building, there ought to be one underneath, too.

But that wasn't the case with the formerly vacant building at 466 King St., and the missing first-floor chimney was far from its only structural problem.

A previous fire several years ago and a big hole in the roof had caused extensive damage and debris toward the rear. A steel column holding up what remained of a center dividing wall had no footing underneath.

A 1976 story on the building in this newspaper said, in a bold headline no less, that the building "Has Problems."

The job of saving the structure fell first to Mike Blanchard of Charles Blanchard Construction Corp.

"The building was to the point where it was in danger of imminent collapse when we started," he says. "It was kind of scary with that chimney. That whole section of the building had started leaning in, and the chimney had started separating from the brick wall."

"It was a rat's nest in there when we started."

His crew used a lift inserted through a gaping hole in the rear to pick debris off the upper floors because it didn't appear strong enough to walk on.

And the greatest drama came during the three days when workers gingerly added support underneath the chimney so they could dismantle it carefully from the top.

"For three days everybody was tiptoeing and speaking quietly, praying for no small earthquakes," he says.

When Blanchard Construction was done with the demolition and stabilization, the construction work became more straightforward. Architect Jimmy Walker of Schmitt Walker Architects designed the steel skeleton that would be the building's new bones and mapped out an interior to suit PeopleMatter, a software firm.

Walker says his goal was to preserve the three walls, essentially all that was left of the three buildings, while expanding the rear to provide a total of 16,000 square feet of space. The architectural scheme, with a four-story addition recessed back from King Street, actually took shape around 2006 before PeopleMatter arrived on the scene. But original plans for a commercial-office-condo redo were shelved by the Great Recession and not resurrected until the software design firm took over.

Walker says the goal was to preserve as much as possible on the remaining walls, including the signature metal cornice and window hoods, while designing its new section to be simple and contemporary "to make it clear what was old, what was new."

Down a landscaped alley just north of the building is its main entrance, a four-story glass and steel form with the steel beams riffing on two steel beams added years ago to stabilize the historic north wall. Those steel beams were kept on the wall, even though they no longer serve much purpose (the structure is essentially a new steel skeleton). "Those (beams) really aren't needed," Walker says, "but it helps tell the history of the building."

Perhaps the most successful aspect of the design is its flexibility going forward. While the building today is one big office, it could be remodeled at little cost to add retail on the ground floor, separate from what's above. Also, the design, especially its alley entrance, was done so PeopleMatter eventually can expand into a new building at 468 King, which is now the single-story Charleston Beer Works.

Nate DaPore, PeopleMatter's president and CEO, says that ability to expand was a plus for this location as well as all the restaurants, shopping and nightlife nearby.

"And personally, I was attracted to the location since I grew up right down the street," he says.

Architecturally, the only sour note is the unnecessarily discordant "FDC" (fire department connection) sign at the corner, a common problem downtown the city's architect Dennis Dowd is aware of and trying to address going forward.

And if that's the only thing wrong, then a lot went right.