Those driving down Charleston’s Cannon Street might think the renovation of the old bank at 544 King St. is, well, rather ordinary.

But those who step foot inside the new Ordinary restaurant will discover it’s anything but.

The 1927 limestone-and-brick building looks much the same on the outside (with only two banners and two sconces added), but its interior has been restored to its original open and impressive proportions, starring a ceiling that’s approximately 23 feet high.

The bank is one of the best small surviving works by Simons and Lapham Architects, downtown Charleston’s most prolific firm in the 1920s and 1930s.

It’s perhaps not as grand as Memminger Auditorium or the College of Charleston’s gym, but its location where Cannon runs into King has made it a major urban focal point for decades.

As architect David Thompson and contractor Mark Regalbuto began, their challenge was to keep the building’s sense of history while converting the former bank into an upscale seafood hall and oyster bar with a top-notch kitchen.

Thompson says his greatest challenge was figuring out how to vent the stoves, a solution that entailed reworking the mezzanine floor section and working around a small office on the mezzanine’s northeastern corner.

But that design work is largely hidden. A more visible challenge was how to treat an SUV-sized vault in the center, rear section of the building.

The team considered converting it into a small, private dining room, but that idea didn’t quite click.

Instead, the door of the safe forms an impressive back drop to the restaurant’s raw bar. Regalbuto’s crews spent weeks removing the rest of its massive concrete and steel structure.

The steel was reused to make the bar along the southern wall. Those looking closely can see “L.W.” and other initials etched into it years ago, presumably by the team that originally installed it. Thompson says it’s his favorite detail.

Overall, there are not a lot of fussy details. The feel is similar in its sparse elegance to FIG, the previous restaurant by chief Mike Lata and his business partner Adam Nemirow.

Thompson notes the larger design challenge also included establishing a sense of symmetry when possible and letting go when not.

The original three large windows along the northern facade were balanced on the southern side with three similarly sized bar cabinets, topped with semicircular glass panels to match the opposite windows.

The booths along the southern half of the restaurant are elevated so those diners’ heads are more even with the people sitting on stools at the bar, while the tables to the north — on the other side of the restaurant — aren’t elevated at all.

There are other subtle details that link the building’s past to its present, including an old teller’s table with a new marble top that now serves as a hostess stand.

Those who visited the bank most recently may be stunned at its transformation, particularly if all they remember was the unimpressive dropped acoustical tile ceiling or its drive-through, both now long gone.

Reclaimed DesignWorks provided material for the floors, stair treads, bench seating, tabletops and bar.

The most intriguing of this is the bartop, which was made from 1950s freight truck flooring, perhaps even from trucks that once carried fresh fish.

The Ordinary will appear more attractive on the outside once the scruffy parking area to the north is replaced with a new building and a landscaped alley that also will provide some outdoor seating.

But inside, the transformation is done.

And it seems fitting that in an era where banking can be done on a computer or laptop, an old, abandoned bank building originally meant to convey security and tradition has been repurposed for an even more timeless purpose: a special place to get something good to eat.

Reach Robert Behre at 937-5771.