Kōenji Station

高円寺駅, Suginami City, Tokyo

Proposal by Iris Lee & Ally Lee

Many of the logics used in the Kōenji Station adaptation were shaped by Okinawa’s climatic conditions, including frequent typhoons, strong winds, and extreme heat. Hybrid pre-stressed concrete (HPC) is manufactured with a polypropylene fiber mixture, which enables architects to design buildings with thinner and lighter structures. This lighter version of concrete traps less heat than regular concrete, an important consideration when constructing buildings in Okinawa. Hana block is another design strategy that encourages airflow via its porosity. Its concrete perforations introduce increased ventilation and allow typhoon winds to pass through safely, while its concrete structure continues to shade intended areas and prevent debris from entering spaces. It was also observed during site visits that, depending on where one stands within a building or in between two walls, certain wind channels are created. These wind channels further promote airflow and cool the environment down. Okinawa’s geographic features also influenced the development of titanium roofing, since its anti-corrosive and lightweight properties combat the island’s salty air and occasional earthquakes. Featuring panels installed using mechanically seamed systems—which fold panel legs into each other to create a locking system—titanium roofs are also more resilient against typhoon winds, as they are less likely to be ripped off. Though unrelated to Okinawa’s climate and geography, the logic behind Food REBORN stems from a sustainability-seeking culture, where producers aim to reuse natural materials and make fabrication processes less wasteful.

We are responding to the dangers in the area surrounding Koenji Station as Tokyo transitions toward a more subtropical climate as a result of global warming. This includes rising wet-bulb temperatures, where high heat combined with increasing humidity reduces the body’s ability to cool itself through sweating, creating dangerous conditions for commuters. Koenji Station is also surrounded by extensive asphalt roads, pavements, and dense urban development, which absorb and retain heat, thus intensifying the urban heat island effect. In addition, a warmer atmosphere holds more moisture, resulting in higher humidity and increasingly intense rainfall events. Nakano City already has a history of flooding due to the nearby Kanda and Zenpukuji Rivers, and more intense rainfall associated with climate change would likely lead to localized flooding around the station. As concern over global warming has grown, the nearby Koenji Hikawa Shrine, Japan’s only Weather Shrine, has attracted more visitors praying for protection, increasing pedestrian traffic through Koenji Station and reinforcing the need for climate-resilient infrastructure.

In a future where Kōenji Station faces risk of flash floods, extreme heat, and increased pedestrian traffic, these Okinawa-derived logics of HPC, hana block, titanium roofing, and recycled materials would focus on reducing the dangerous heat conditions and creating increased airflow within the station. By angling HPC and titanium panels along the facade of the station platform, the space within can welcome more wind. Furthermore, if hana block were to replace platform railings, then funneled cutouts in the design patterns of the hana block could allow wind from passing trains to flow through and into the platform area. As rain flows down from the roof and wind blows through these blocks, the air that reaches commuters becomes imbued with a cooling effect. A raised platform ground—as observed at the Nakamura Residence and in other traditional Japanese architecture—could also allow for more ventilation, as air is able to pass through and below the station. This raise would also aid any flooding, since it would open areas for water to fill without flooding over the tracks. Regarding the roof, along with lightweight titanium panels that are mechanically seamed to prevent getting ripped off and flying away in the typhoon winds, the roof would also be accordion-shaped like a zig zag. This design was inspired by the terracotta tiles of Okinawa and their temperature circulation capabilities via the peaks and valleys they created. Much of the basic furniture of the station is intended to be made with recycled materials from plant byproducts. This would at least reduce the carbon footprint of the station by a fraction.

The primary limitation of our design translation is cost. Titanium roofing and facade panels require a high initial investment, despite their exceptional durability and low maintenance over time. Similarly, using HPC would involve significant material costs and the expense of producing custom molds for the Hana blocks. Although these materials offer long-term benefits, their upfront costs may limit widespread implementation.

Process sketches by Iris Lee & Ally Lee

Read more about Iris Ally's proposal here.