Exterior, House Building Type, and Wood Siding Material “For the structure, Mapos devised a hybrid system of concrete, steel, and Structural Insulated Panels (SIPs),” co-principal Caleb Mulvena says. “Each was strategically utilized to create a lightweight, rigid, and highly energy-efficient shell.” Fiber cement-board cladding and a steel standing-seam roof act as the structure’s envelope.  Future home exterior from Hudson Valley Dream Retreat