This barn houses the family's five horses. The roof is made of metal reclaimed from nearby ranches in Montana and Wyoming. "On the driveway, we used gravel instead of asphalt to keep the rustic, historic feel," says Frackiewicz.If you're interested in building sustainably but worried about costs, Frackiewicz advises looking at it this way: "To spend 1 to 3 percent on the front end and save 40 to 65 percent in operating costs is a great business decision and a good legacy for the environment."See more guides to modern rustic design