The typical exterior finish for homes built with insulating concrete forms (ICFs) is stucco or synthetic stucco. This 10,000-square-foot beachfront home in St. Augustine, Fla. proves that there are other options. With a structural frame of 9-inch and 11-inch ICFs from Reward Wall, the exterior surface starts with 5/8-inch CDX plywood attached with stainless steel screws to the fastening strips in the ICFs. Over that, home builder Barry Tully's crews (Tully Builders, St. Augustine, Fla.) installed a layer of water and ice shield and finished the home with cedar shake shingles, traditional for Florida beach houses. “As a custom home builder of 28 years,” says Tully, “I had never built an ICF home, but I was extremely pleased with the final product.”
ICF construction was chosen to counteract the very high wind loads the house is likely to experience on the Florida coast. The ICFs were constructed by Force One Walls, Jacksonville, using Reward Walls' bracing system, which keeps everything level and plumb, and also provides a bracket for scaffolding. Workers stacked the blocks and filled them with concrete in 5-foot lifts. Crews formed and poured interior concrete beams and placed wood trusses for the roof. “ICF construction could be a nightmare without the right crew,” says Tully, “but with these guys everything went smoothly.”
On the interior, crews cut channels into the foam facing for electrical wiring, then attached drywall directly to the ICFs. For the attic space, Tully sealed it and sprayed in closed cell insulation. This created a very quiet home and also led to another advantage—unlike most beachfront homes that get dusty quickly from wind blown beach sand, this home is so tight that it is virtually dust-free.
The interior woodwork was made from reclaimed hard pine from the famous Ponce de Leon Hotel, built by Henry Flagler in 1888. Flagler, a founding partner with John D. Rockefeller of the Standard Oil Company, moved to Florida in the late 1800s and built some of its most famous hotels.
“We don't have any other ICF homes in the works at the moment,” says Tully, “but I would gladly use them again since the use of concrete in residential homes is structurally superior, extremely efficient, and is adaptable for many exterior finishes other than stucco.” Photos courtesy of Tully Builders, St. Augustine, Fla.