What appears as two buildings from the street front serves as an illusion for the horseshoe-shaped layout of the Tenjincho Place Complex in Tokyo. Designed by Hiroyuki Ito Architects, the apartment building is in an area transforming its character. As the architects mention in a press release, numerous hotels in the area have been replaced by apartment complexes, reflecting the ever-evolving nature of the city and its growing need for housing. Located along the approach to a renowned shrine and on the edge of a plateau in the Yushima prefecture, the architects were faced with a particular challenge for the housing design: a flagpole site surrounded by high-rise apartment buildings on three sides, curtailing natural light and ventilation from entering the site as well as views to the outside for the potential apartment designs.

The unique shape of the building that wraps a curved volume around a central void is meant to counter this issue. The courtyard created by this form and designed 10m below the street entrance becomes an ingenious way to allow light and wind circulation throughout the complex’s residential architecture. Further, apart from serving a strictly functional purpose, the courtyard design creates a space where residents can gather and relax. As the Japanese architects mention, “The cast of the courtyard [brings] play and depth to an imposing space meant to allow for a break in every day of its residents and visitors.”

Its design is meant to evolve into a public space in the future, with proposed activities such as a co-working space, store, café, or market planned depending on the evolution of the surrounding area. Currently, it’s accessible only to residents of the 35 units of the complex. Within the structure, each apartment is a single-bedroom unit and enjoys views of the courtyard as well as the outside, ensuring light and wind circulation. A frame structure for the exposed concrete building with the beams of each unit arranged radially at equal intervals guided the individual interior layouts of each residential design. Furniture and washbasins are built into the spaces between the pillars.

The housing complex was built on the site of a former hotel with the clients wanting to reconfigure the site’s function. The design scheme is rebuilt with the same floor area ratio as the existing hotel. With each unit opening into the courtyard, the architects underscore that a key factor in designing was to create a comfortable living environment despite being in a context with insufficient natural light. The horseshoe shape also allows the architects to minimise the number of corridors within the structure, with corridors built to connect the two arms of the horseshoe or spanning half the length in a staggered manner.

The end of each corridor also becomes a maisonette residential unit that spans two floors, thus effectively dividing the corridors and allowing for clear circulation through the building. Each floor is subdivided into at least two individual units and a maisonette, with breaks within the layout serving as balconies; either for individual units or common to two residences. These openings allow light and air to enter from various directions around the courtyard, while also hosting greenery, making the concrete architecture seem lively.

The courtyard design ensures that even the slightest light enters, as is evident in the pictures. To achieve this, a strategy the architects utilised for the façade design was the application of a rough, grooved texture ‘suitable for a 30-meter-high wall [that would] enhance the perception of even the slightest light,’ as they elaborate. The formwork for the concrete was suitably designed from Japanese cedar logs sourced from the ‘Wooden Station Project’ in Sammu City, Chiba.

"This initiative aims to sustain healthy forests by acquiring thinned wood and forest residue from forest owners at a collation point known as the ‘Wooden Station’. During construction, logs were sliced into 15mm pieces, retaining the bark on one side, and affixed onto plywood to create the formwork. This technique allowed us to capture the organic shapes and contours of the logs into the concrete,” they explain. The result is a stunning irregular, corduroy-like finish that enhances the interplay of light and shadow in the courtyard.

The architects mentioned that while the project proved challenging given the shape of the site and the slope, the hope was to create a unique place, “a residential architecture that would be comfortable to live in, and where everyone will be able to experience the pleasant feeling of the breeze even when there is no wind around." In a rapidly urbanising and dense context like Japan's capital, we need solutions that not only maximise the number of homes we build but do so in a manner that emphasises well-being and the human. Through a design that utilises a tight plot and yet manages to create a sense of lightness, the courtyard architecture of Tenjincho Place could well become a prototype.

Project Details

Name: Tenjincho Place
Location: Tokyo, Japan
Year of completion: 2023
Site area: 780 sqm
Built-up area: 2450 sqm
Design team: Hiroyuki Ito, Junko Uehara
Consultants:
Structural Engineer: Shuji Tada Structural Consultant
Mechanical Engineer: Tetens Engineering Co., Ltd.
Electrical Engineer: EOS plus Co., Ltd
Landscape Architect: Kayoko Nagayama Garden Design & Construction
Contractor: Sanyu Construction Co., Ltd