Green By Design Sylvain Côté took a unique eight-sided house and rebuilt it green, focusing on the massive stone chimney and adding reclaimed wooden rafters and floors and efficient energy systems.

The pink and blue winter sunset glows spectacularly over Lake Truesdale. But even with the temperatures dropping, Sylvain Côté and his family will be cozy inside. The green design and construction applications Côté has included in the gut renovation of his 1980s, 3,750-square-foot octagon house make sure of that. In March of last year, he and his family finally moved in to the house, the first home they've owned.

Côté, a home builder originally from Quebec, Canada, retains his French accent but is completely fluent in "green," the growing field of sustainable, energy-efficient building practices. Côté's research for the expansion and redesign of his family's home guided him to the experts, the organizations, and the materials and techniques he used to bring this striking house in South Salem to Energy Star certification. The brass Energy Star plaque on the front door means the house is a minimum of 30 percent more efficient than a home built to the New York State Energy Code.

The shape of the home posed many design challenges, which Côté met with ingenuity, including suspending the catwalk with an iron tie connecting ceiling rafters. Natural light shines down from the cupola.

"Some builders say they want to be energy efficient, but they don't take care with the details. Some are just happy to get Energy Star rating," says Tony Lisanti, a certified HERS (Home Energy Rating System) rater and director of energy sales for Robison Energy in Elmsford. "But with Sylvain, there was no question: He was going to make his house as energy-efficient as possible."

"I had been 'green' for a while without even knowing it," says Côté. In late 2003, while preparing for the renovation of his house, which eventually took 28 months, he learned about the U.S. Green Building Council. He attended the USGBC's first annual International Conference and Expo in Austin, Texas, where, he says, he felt like "a kid in a toy store." Subsequently, when he encountered an unexpected last-minute permitting delay, Côté went back to the drawing board and spent an additional 1000 hours refining his drawings and teaching himself about green options.

The delay turned out to be a blessing in disguise. Côté feels the house is much improved as a result. And now Côté can offer, through his high-end renovation business, Absolute Remodeling (www.absoluteremodeling.com), first-hand expertise in these increasingly bottom-line-favorable features that save energy and money, reduce maintenance, and enhance design.

We began our house tour outside the house, where Côté opted for synthetic materials, for their durability. These include a 100-percent-plastic, no-maintenance, no-emissions "cedar shake" siding made by Nailite and a synthetic "slate" roof from DaVinci Roofscapes, both guaranteed for 50 years. The trim, made by Kleer Trim, and the decking, by EON, are guaranteed for life. "I look for materials that are long-lasting, recycled, local, or reclaimed," says Côté. "Outside, it's all engineered. Inside, there are three themes: wood, stone, and wrought iron—raw materials."

The floors are made of reclaimed wood and finished with natural tung oil instead of polyurethane. In the master bedroom, the bed and headboard, built from leftover flooring, sit against the massive stone chimney, upon which the entire house centers.

The house centers on a huge chimney with two double-sided fireplaces. When Côté decided to add a third story to the original structure, he faced a number of challenges, including extending the chimney 15 feet. The total height of 45 feet required 45 tons of stone, cinder blocks, and mortar. Fortunately, all of the stones needed were reclaimed from existing stone siding. All that thermal mass helps the interior stays cool during summer and warm during winter. Côté installed wrought-iron tension rods to hold up the catwalk on the third level, which opens the space and lets in more light. Ten of the original roof beams became the interior structural rafters, some of which were boxed with antique lumber from Reclaimed Lumber in New Haven, CT.