The atmosphere feels curiously different inside the remodeled Craftsman house in Northwest Washington, D.C., where Vanessa Bertelli and Stefano Negri live with their three children. The heavy humidity outdoors is replaced with a rush of clear, fresh air. The city noise evaporates into silence once the door is closed. In every room, from the basement to the attic, the temperature remains surprisingly consistent. The building, decorated in a Scandinavian minimalist style, has white, uncluttered walls and exposed wooden ceilings and looks like any well-designed home with fine modern touches. But this is no ordinary house.
