When Oregon, Ill., builder Rick McCanse first encountered his future clients Kent and Kathy Lawrence, it didn't take him long to decide he wanted to work with them. "I knew we'd get along famously," he says. Not only did their laid-back personalities mesh well with his, but they also shared his concern for the environment. The Chicago couple had set up their own 55-acre nature conservancy on their land in Oregon, about 90 miles west of the Windy City. And they'd hired appropriately named architect Thorn Greene to design a weekend house, one that would demonstrate the benefits of green building.

McCanse and his family live in an eco-friendly passive solar home he built in 1979 using salvaged lumber and other recycled materials. So his experience dovetailed nicely with Greene's passive solar design for the Lawrences' house, known as the Kickapoo Dwelling after the American Indians who once inhabited the area. The plan's major passive solar feature is a long, glass-walled hallway along the home's southern edge. Sunlight streams in through the glass and hits an 8 1/2-inch-thick stone wall, a thermal mass that holds the heat and radiates it throughout the day and night. The architect angled the home's standing-seam metal roof and exterior trellis to protect the hall from excess sun during summer while still letting in the lower winter sun. The glass wall's operable upper and lower windows work with the clerestories atop the stone wall for cross-ventilation.