South Carolina’s Low Country is a place of rare, delicate beauty. And its salt marshes are incubators of that beauty—precious environments where the ebb and flow of tidal creeks support undulating seas of grass and provide habitat for a rich variety of living creatures, from humble sand crabs to majestic blue herons.

As luck would have it, Frank Harmon, an architect from Raleigh, North Carolina, had the opportunity to build in just such a lush setting. His client, an avid birdwatcher and fisherman, had acquired a lot overlooking Shem Creek in the environs of Charleston. As Harmon saw it, the site was so extraordinary that his goal in designing the waterfront house boiled down to one thing: tread lightly. In doing so, he strove to create a shelter that would simulate the feeling of living outdoors.

To bring the outside in, Harmon created a long, modern pavilion with all the functional spaces clustered beneath a single shed roof. The slender floor plan allows all the rooms (save for the occasionally used guest room) to enjoy views of the marsh, while also reaping the benefits of natural light and ventilation. At the core of the house, Harmon placed a large open space exposed to the world through a wall of glass extending 12 feet high and nearly 70 feet long. “The primary issue was how to get a view out over the saltwater marsh,” he explains.

The free-flowing central space consumes almost half of the floor area in the 2,500-square-foot residence. “It’s a typical gesture of mine,” says Harmon. “I like for 50 percent of the house to be one space.” Living and dining areas, an open kitchen, a nook for a desk and an entryway all fit seamlessly in the loft-like room, where a comfortable rhythm is established by regularly spaced steel columns and overhead beams. “I wanted a house with a lot of light and a combined living room and kitchen,” says the owner. “I don’t like chopped-up spaces.” Walls made of clear pine and a ceiling of tongue-and-groove decking give the room a warm glow in the afternoon sun.

High along the wall opposite the large windows, a narrow loft hangs from three-quarter-inch-diameter steel rods. This gallery penetrates the house from end to end, providing a place for the owner to display his collection of vintage John James Audubon bird prints while offering easy access to the seven-foot-tall, operable panels that swing open to allow prevailing southwesterly winds to flush the house.

While the residence is designed to embrace nature, its openness also created a vulnerability to the torrid summertime heat and the frequent threat of hurricanes along the Atlantic coast. With that in mind, Harmon built protective layers around the house. The key invention was a contemporary interpretation of the ubiquitous shutters on Charleston’s historic homes: a series of 500-pound, hand-fabricated steel screens. Hinged above a porch that fronts the southwest-facing glass wall, the screens are built of hearty metal frames that support perforated-metal panels—the kind often used for catwalks in industrial buildings. Made of galvanized steel, they bear up well under wind-borne, corrosive salt.

In their horizontal, open position, the screens create a continuous canopy that shades the house in spring and fall. Set vertically, they shield the windows from flying debris or, in the summer, block the intense late afternoon sun while still allowing breezes to pass through. “They are almost like visors,” says Harmon, who credits fabricator Christian Karkow with solving the details of a counterbalance mechanism that lets the panels be operated by a single person.

Other functions of the single-story house take a back seat to the experience of the great room. In addition to a spacious master suite, Harmon provided for a sizable guest room and a convenient laundry room—all gathered at the south end of the house. Placed at the northern end are an additional bedroom for the owner’s college-age son and a large workshop equipped for serious tinkering on vintage cars and hand-made boats. “My son really wanted a hydraulic lift,” notes the owner. “He’s in industrial design school, and wants to design cars someday.”

On the rear of the house, a screened porch offers another place to escape, and a roomy wooden deck runs the length of the house. Harmon built the deck of a sustainable Brazilian hardwood called îpe. He avoided installing a tile or concrete terrace because he knew it would absorb and radiate heat during the hot season, when a cooling effect is more desirable. Wood decking also surrounds the exercise pool, which parallels the house. “I really like the location of it, because it allows reflections of the sky into the house,” says Harmon. “I also like the idea of swimming laps parallel to the tidal flow of the creek. Something just seemed appropriate about that—like being in sync with nature.”

Seen from the front, the low-lying house appears quite solid, with ground-level walls sheathed in fiber-cement panels. Tall clerestory windows on the balcony level spill light into the great room, while translucent polycarbonate panels placed to either side of the glass admit softer light into the bedrooms.

Towering, 200-year-old live oaks, a veil of Spanish moss and a smattering of palmettos and pecan trees obscure the house from its residential street. Even from the curve in the driveway loop, the broad house blocks the marsh view. “That was the goal,” Harmon confesses, “to make a long, sleek building that forms a gentle wall between you and the creek. You go through the wall, and only then is the view of the creek revealed. I always find if you can conceal a view before you get in the house, it makes the view quite special.”

Vernon Mays is curator of architecture and design at the Virginia Center for Architecture and editor of Inform magazine, published by the Virginia Society AIA. Photographer and musician Richard Leo Johnson is based in Savannah, Georgia.