LEED? Lame. Passive House? That's past time. Built Green 4-Star? Boring. Want to be like the cool eco-friendly kids? Well then you better move into a Built Green Emerald Star home. Right now, there's only one of them in Seattle and you just missed your chance. Dwell Development sold the 2,218-square-foot Ballard house at 1749 N.W. 61st Street on Monday for $850,000. What makes a home Built Green Emerald Star? There's a whole checklist of energy-efficient and eco-friendly things that go into it.