The 57-foot panoramic window was inspired by traditional "Engawa" houses in Japan. Koolhaas preserved its minimalistic aesthetic by camouflaging the supporting wood beam in white laminate and nestling it in the space just beneath the ceiling. He also kept the beam small by installing a tree-like column to help carry the weight of the second floor and roof. "The actual tree that was used for it came out of the garden," the architect says. "In this way, the small forest in the garden continues into the house."