Geographically and ideologically, South Carolina’s Dewees Island is a place unto itself. Separated from the mainland by the silvery blue fingers of the Intracoastal Waterway, the island community is designed to preserve its pristine natural beauty. With a serious commitment to protecting the fragile barrier-island ecosystem, Dewees Island residents are a step ahead when it comes to environmental awareness. And that made it the perfect place for John and Sue Porretto to build their “heirloom” home: one that could withstand the rigors of a coastal environment, outlast a 30-year mortgage and be passed on to children and grandchildren.
John and Sue’s timber-framed house, enclosed with structural insulated panels (SIPs), was constructed to the highest energy-efficiency and sustainability standards and designed to withstand a hurricane with 145-miles-per-hour winds. Because beach erosion and accretion are anticipated on Dewees, which is accessible only by ferry, homes nestle deep into the landscape, making a small footprint on the island.
The Porrettos, who divide their time between Dewees and their home in Houston, spent years conceiving and developing their island retreat, a cypress-clad masterpiece that rises three stories above the indigenous vegetation surrounding it. Inside, the exposed post-and-beam structure made of standing deadwood, reclaimed heart-pine flooring and clay-covered walls give the living areas a traditional and earthy feel. Large windows and French doors draw the eye to stunning marsh views.
Environmental rap sheet
Building sustainably was the Porretto’s top priority. As the chief operating officer of a large academic health center, John had persuaded the board of trustees to build the University of Texas School of Nursing to the highest green standards.
“I was confident an investment in sustainable building methods would pay for itself in about three years,” John says. “And it would continue to benefit the university through reduced utility and maintenance expenses for the life of the building.” The result was the largest green academic building in the Southwest, recognized by the American Institute of Architects as a Top 10 Green Project for 2006.
For their own home, the couple spent a lot of time researching the construction process and the interrelatedness of systems and materials. “After meeting with several home builders, it became clear to us they were competing on price rather than quality,” Sue says.
Unwilling to compromise, the Porrettos built their home themselves. John earned his South Carolina residential contractor’s license, and the couple hired Houston architect Roger Rasbach, who completed the design of their home shortly before his death. The Porrettos teamed up with Riverbend Timber Framing to construct the post-and-beam structures and engineer the SIPs.
Typical of coastal construction, the house is built on stilts; the third floor affords spectacular views of the Intracoastal Waterway. The interior’s many exposed timbers are connected by pegged mortise-and-tenon joinery, much like that found in fine furniture. None of the wood (except the kitchen cabinetry) has been treated with chemicals or stains, which helps maintain healthy indoor-air quality. German Weru windows and doors are highly efficient; their solid engineering actually contributes to the home’s wind resistance.
All wood in the home is either reclaimed or from standing-dead trees. The unsealed, beveled cypress siding allows the wood to breathe in the humid coastal environment, reducing moisture concerns. The durable, slatelike composite roofing is composed of at least 50 percent recycled material and is recyclable.
The Porrettos installed a closed-loop WaterFurnace geothermal heat and air conditioning system, which has helped lower energy bills. The geothermal heat pump technology taps the earth’s near-constant temperature, circulating a water-based solution through underground pipes to transfer heat to or from the home, thereby moderating the temperature.
Careful synchronization of room sizes and SIP dimensions effectively eliminated any construction waste. On Dewees Island, this was particularly significant because all supplies must be carried on and off the island by boat. Until the very end of the job, the Porrettos didn’t even have a Dumpster on site. All leftover materials were recycled into the project or chipped and used as mulch on the property.
The home’s décor is inspired by natural materials, and the couple repurposed leftover pieces of granite, quartz and wood that might otherwise have ended up in the landfill. A reclaimed wrought-iron and tortoiseshell-glass chandelier illuminates the third-floor foyer. A large mansard-inspired fireplace, made of honed stone and covered with clay, is the focus of the gathering room, which is open to the dining room and kitchen. Two sets of French doors flanking the fireplace lead to one of the four spacious porches, which augment the home’s living space in the temperate Southern climate.
The couple chose Energy Star kitchen appliances and water-saving bathroom fixtures. They installed a highly efficient plumbing system by Manabloc, which allows for independent control of each hot- and cold-water line. The system also requires less labor and materials because it employs wire tubing rather than pipes.
Because it’s common for two or more families to share a vacation home on Dewees Island, the second floor is designed to be fully self-contained with a private entrance, service kitchen, laundry, living and breakfast areas, and three guest bedrooms. Two spacious porches on this level encourage indoor-outdoor living as well.
A new preservation paradigm
Dewees Island was developed by one of the world’s leading environmental developers, John Knott of the Noisette Company in North Charleston. His vision led to environmental protection covenants that limit the number of homes to 150 and stipulate that only 7,500 square feet of each lot can be disturbed by construction. Houses must be surrounded by native vegetation—no lawns are allowed. In addition, cars are banned from the island; residents navigate in electric golf carts.
The Porrettos are passionate about their commitment to sustainability. They and other Dewees Island residents share a daily devotion to living in harmony with the natural world, and residents regularly fish, bird-watch and participate in educational outreach programs offered through the onsite nature center.
When John and Sue Porretto board the ferry to head back to Houston, they know their barrier island home can withstand almost any condition nature sends. “Finding the right place for our retreat was the most important decision we made,” Sue says. “Dewees Island is such a special place. Our pristine beaches and breathtaking skies provide a welcome respite from life’s fast pace. Every time we leave, the longing to turn back prevails.”