“Self-consolidating concrete, already integrated into a lot of commercial and industrial work, now is gradually being integrated into residential work,” he says. “I decided that the best way to educate people about the different aspects of using concrete in a house was just to build a good example.”

For Harrison of Harrison Design Associates, with offices in Atlanta and Santa Barbara, designing another East Coast beach house was not unusual. “Often, the form and style of a contemporary house is best executed in concrete,” says Harrison. “You can create just about any design or shape you want. The only limitation is the craftspeople's ability to make the forms.”

The concrete home, nearly completed, offers all of the safety and cost advantages of the material of choice—concrete.

Here, Harrison used curved forms, glass, symmetrical openings, and flow-through interior spaces to capitalize on the unique properties of concrete construction. The house's entranceway is a 37-foot-high, 20-foot-diameter concrete and glass greenhouse tower, with a 5-foot-wide circular porthole cutout near the top. Because the living space is set 15 feet above the flood plain, as required by federal building standards in coastal areas, visitors ascend to the main floor by a glass and steel elevator or an elegantly curved stairway.

“Big, open, curved stairways are hard to execute in wood framing, but they work well in concrete,” says Harrison. “You have to coordinate the design with the structural engineering, paying attention to the basic organization of the house.” The team admits the port-hole was a challenge. Like the stairs, the massive, curved, 37-foot wall with its distinctive cutout was poured using SCC.

Under the watchful eye of Howard's skilled crew, the SCC yielded a highly workable mix requiring no vibrators to create big sections of smooth, honeycomb-free walls, ideal for creating the dramatic porthole centerpiece where visitors see through the house to the water. Using pre-stressed concrete deck spans for the flooring system had distinct architectural advantages, too. The hollow-core, 4-foot-wide concrete deck panels are 8 inches thick and can span up to 40 feet. “The large spans allowed us to create lots of clear, open spaces,” Harrison explains.

Concrete construction contributes integral structural benefits often seen as desirable but expensive add-ons in conventional wood frame construction: high R-value insulation, soundproofing, fireproofing, and exceptional durability. “Concrete gives you a structure that's dimensionally stable and also fireproof,” Harrison says. “You don't have the expansion problems you have with wood—the shrinking and moving with moisture—and it's quieter. Because of the density of the materials, there are no vibrations.”

Concrete construction's costs have become competitive with wood in coastal areas, given the increased demands for hurricane resistance. “If you compare structurally equivalent walls at equal wind loads, such as a 100-mph wind resistant wall, concrete is cost-competitive with wood framing,” Howard says.

— Faye Goolrick is a freelance writer based in Atlanta.