Guy Nordenson and Associates was responsible for the preliminary design of the structure as well as the detailed design of the glass wall structures facing the garden and the stairs and other exposed structures. The main structure is steel, with column bays 26ft by 64ft, and includes an office tower. One important feature is the use of an outrigger truss linked to the core wind bracing to transfer a hung column over the second floor contemporary art gallery, allowing for a full 200ft by 54ft column free space. The glass wall structure is made of 2-1/2in by 7in solid steel mullions spanning 60ft and stabilized elastically.