Construction is now underway on OH-1, one of the largest redevelopment projects ever undertaken in Japan’s capital. Designed by the architecture firm Skidmore, Owings & Merrill LLP (SOM), the project comprises two high-rise buildings with a total floor area of 360,000 square meters, and a landscaped public open space. Prominently located in Tokyo’s Ohtemachi district and adjacent to the Imperial Palace East Gardens, the project covers a 20,000square-meter site. The OH-1 development reinforces the status of Ohtemachi as a premier international business center, while introducing new vitality to the area. Its mixed-use program includes commercial office space, a luxury hotel, retail, cultural facilities, and improvements to the public realm.
A recent groundbreaking ceremony marked the start of construction and celebrated the design of the project. Initiated by the real estate developer Mitsui Fudosan, the OH-1 project will create a new corporate headquarters for Mitsui & Co, one of Japan’s largest trading companies. This project continues a history of collaboration between Mitsui Fudosan and SOM, which have together created a series of major developments in Tokyo totaling more than 2 million square meters. These include Tokyo Midtown, a 563,000-square-meter mixed use development completed in 2007, and the Nihonbashi 2 Redevelopment, currently under construction. SOM’s design approach—balancing tradition and innovation—is reflected in the design of the two towers, which differ in their scale, massing, and materiality. Tower A, which faces the Imperial Palace, is the lower of the two buildings, and its design responds to the history of the site.
At 160 meters tall, the tower’s scale harmonizes with the adjacent commercial buildings fronting the Imperial Palace East Gardens. The tower’s design, in its detailing, is inspired by traditional Japanese craftsmanship and woodworking techniques, brought to a contemporary interpretation by the use of granite and glass cladding. Tower B, which faces the Ohtemachi district, will rise to 200 meters. Clad in glass and steel, this tower establishes a strong presence on skyline as an emblem of contemporary Japan. Both towers are designed to allow for natural ventilation, and they include a range of sustainable design features that reduce their energy use. The OH-1 project creates a significant open public space on the western edge of the site, facing the Imperial Palace East Gardens. Covering 6,000 square meters, this park will be landscaped with native trees, and will include a reflecting pool and a plaza to accommodate a variety of outdoor events.
The park’s design also preserves and enhances the setting of Masakado’s Shrine, a historic cultural monument located on the site. With direct access to multiple Metro lines, the development is fully integrated into Tokyo’s public transportation system. In addition to offices, hotel, and commercial amenities, the OH-1 development includes a multipurpose hall overlooking the park and plaza area. Equipped to host a range of events, from international business conferences to musical performances and entertainment, this amenity contributes to the project’s goal to enliven the Ohtemachi district as a cosmopolitan hub and cultural destination. With construction underway, the OH-1 project is scheduled for completion in 2020. Source by SOM, photos by Mitsui Fudosan | Mitsui & Co. and images by Methanoia, Courtesy of SOM.