Exterior, House Building Type, and Wood Siding Material The home comprises three structures: a main house, a garage, and a studio for resident Elina Försti, an artist. Local spruce cladding, metal standing-seam roofs, and aluminum frames mean the entire complex is recyclable. “Right now, it all looks very polished, but in the future it will develop a nice patina,” Lassila says.  Photo 6 of 8 in This Battery-Powered House Never Runs Out of Juice