At 4,100 square feet, Dee Gunn and Susan Preston Gunn’s Orange County home manages to display an elegance that is both casual and cozy — and green.The house in the Walnut Cove development, surrounded by Triangle Land Conservancy property, is the last house to be designed and built by local architect John Hartley, who died in June.“John designed and built beautiful homes,” Preston Gunn says. “From almost every room of the house you feel as if you’re surrounded by the natural elements.”Built on a sloped, wooded lot, the house features a walkout basement and first and second floors that seem perched in the treetops. The feeling is even more apparent when standing on the portion of the wraparound deck that pushes out into a V over the woodland. The deck, with plate glass instead of ballisters under the railing, is just one of the many design features that bear Hartley’s mark and his desire to blend structures with their natural environment.“He was an unbelievably spectacular builder,” Gunn says.The couple, who married two years ago, moved into their home in March. They seem to love every inch of it — from the see-through gas fireplaces to the wood ceilings, stone mantle and extraordinary, colorful mosaic (complete with a small bud vase and glass shelves) on the sunroom fireplace outside their bedroom. But what they love most may be the home’s sustainable features.“There are a lot of things you can do that are just remarkably easy,” Gunn says.Check out some of the many green features in the couple’s home.