Piano designed sand-casted ductile iron trusses to support both the Menil’s roof and the ferro-cement sunshades. Each truss member’s cross section changes along the length of the member. The member is thickest at its connections and thinnest at the member’s middle. It transitions between the two geometries fluidly. The shape making of the truss members would not be possible in the traditional rolled or extruded processes of forming structural metals; instead it is only possible through casting metal.