Urban Street-Shading in Tokyo

Proposal by Daisy Fallon & Nana Requeno

In Okinawa’s subtropical climate, shade greatly impacts one’s ability to withstand the heat. Throughout the course, we noticed that walking in the shade was far less exhausting than walking in the sun; long days outside were quickly improved by finding a shady rest-stop. In Okinawa, we observed both natural and built shading mechanisms. In the case of Naha City Hall, creating space for flora on the facade and providing the conditions for flora to thrive shaded the interior and beautified the building. We were also inspired by built shading mechanisms, like arcades and street canopies. We noticed that in Nago, street canopies were used in wider, two-way streets. Wide streets don’t have shading from surrounding buildings like narrow streets do, and this strategy made navigating the city much more bearable. We were particularly interested in shading strategies that incorporated both natural and built elements. Nago City Hall uses concrete canopies, and the building’s design creates the conditions necessary for flora to overtake the canopies. We noticed that the combination of natural and built shading was optimal in creating shade in Okinawa.

While quiet, narrow streets have built-in shading from surrounding buildings, wider streets with two-way traffic remain largely unshaded. As temperatures rise, improvements in street-shading will promote urban livability

- More comfortable walking conditions

- Shaded bus / rest stops

- Improved climate in ground-floor storefronts and restaurants

In Tokyo, the busiest streets are far wider than any street in Naha or Nago, and therefore receive even less shade from surrounding buildings. These streets are already less bearable than the shaded streets, and a future subtropical climate would exacerbate these conditions. We wanted to bring the Okinawan street-shading strategies to Tokyo. Street shading would improve everyday urban conditions, and also help cool first-floor storefronts and restaurants. With Japan’s aging population, shade is increasingly important in ensuring that the elderly can live comfortably and independently. The density and scale of Tokyo introduces additional considerations. Streets are much more crowded, so while canopies in Nago covered only the portion of the sidewalk next to the building, canopies in Tokyo would have to cover a much larger area. Tokyo’s scale also means that there are many more streets to cover. We believe that focusing only on the busiest streets would still make a huge difference in improving urban livability. Finally, Tokyo has much more architectural diversity, so we would have to create a design that could be attached to different building materials and types.

We wanted our canopy design to provide the environment for plants to flourish, but also have an impact without flora. We noticed that flora didn’t always behave as expected in Okinawa, so we wanted to ensure that our canopies would be effective without flora, and flora growth would only bolster their efficacy. From observing integrations of natural plant life within urban contexts, we noticed that it was easier to manipulate growth directions if the underlying structure had ample curves. Straight edges and harsh corners were prone to maintenance difficulties and could lead to poolings of unwanted materials that are hard to clean. Further, curved structures also provide a gentle surface for the plants to grow on and aids with drainage as we observed with the arcade roofs. We chose galvanized steel because it requires less maintenance and does not leave stains compared to other metals that create their own patina when exposed to humid climates as we learned at the Okicom construction site. We hope that our design would require minimal maintenance while withstanding the conditions of a subtropical Tokyo.

Read more about Daisy & Nana's proposal here