645,000 square feet / 60,000 square meters
The NTT Headquarters is a 30-story tower that includes corporate offices, a six-level below-grade telecommunications center with telecommunications systems and equipment, a conference center, executive offices, and dining facilities. Attached to the tower is a 4,180-square-meter Special Purpose Building. The two buildings are linked at a mezzanine-level by a pedestrian bridge that overlooks an open garden.
The complex forms an extension of Shinjuku, a cultural and business district. The design responded to several restrictions, including a 127-meter height limit and a requirement that 20 percent of the site be dedicated to public open space. Other challenges included an elevated highway to the south of the site, two microwave corridors, and accommodating transmission equipment and emergency helicopter landing on the roof.
A fan-shaped block of offices is
oriented toward the interior garden and the long views. Support facilities
occupy the remainder of the allowable triangular envelope. The office portion
of the tower is organized with horizontal windows to take advantage of the
panoramic view. Windows are protected by four rows of projecting sunshades per floor. These sunshades accentuate the horizontality of the windows, modulate the facade and animate it with shadows and highlights. The tower features a curved, metallic curtain wall.
The Special Purpose Building has a wall of Minnesota stone tightly curved to the street and open to views of the interior garden. The eastern side of the building, clad in green Vermont slate, is anchored by a vertical volume with rooms for special functions. The Minnesota stone wall is continued in front of the Tower, diminishing its impact on the sidewalk. A wall screens a parking lot and an automobile entrance and drop off. The garden is used for recreation, exhibitions and performances. It has trees, a fountain, a wood bridge and a fence of composite materials including wood and steel.
In 1997, the NTT Headquarters received an Honor Award from the AIA Connecticut.