In Tokyo’s dense Nakano district, Ryuichi Sasaki Architecture has completed SHIN NAKANO trapezoidal, a compact residential building that translates the hidden geography of the Musashino Plateau into architecture. Also known as GRANTAGE SHIN NAKANO, the reinforced concrete development contains 11 residential units across five above-ground storeys and one basement level.
Rather than treating its constrained urban site as a purely practical challenge, the project uses facade reliefs, openings, materials, and filtered light to evoke the landform beneath western Tokyo. The result is a building whose identity emerges through repeated encounters, from the street elevation and entrance to its staircases and private interiors.
A Trapezoidal Motif Rooted in Geography
The building stands near the center of the Musashino Plateau, a roughly 700-square-kilometre landform bordered by rivers and supported by abundant groundwater. Although this landscape has influenced settlement around Tokyo for centuries, its scale and form are rarely visible from street level. SHIN NAKANO trapezoidal turns that concealed context into a recognizable geometric motif.
Trapezoidal shapes are cast directly into the street-facing concrete frame using purpose-made formwork. Stainless steel elements, windows, and finely textured concrete interact with the relief, allowing the elevation to appear different as daylight, reflections, and weather conditions change. The motif is embedded within the building rather than added as surface decoration.
Geometry Continues Through the Shared Spaces
Inside the entrance, trapezoidal wall columns and patterned tiles extend the facade language into three dimensions. Their alternating surfaces generate soft shadows that recall light passing through foliage. This effect continues along the common staircase, where grated treads and geometric openings produce a shifting pattern of light and shadow.
Lighting designer Natsuha Kameoka of Lighting Sou adapted the same visual rhythm for evening use. Artificial illumination emphasizes the relief without overpowering the concrete surfaces, helping the circulation spaces retain their quiet atmosphere after sunset. The repeated geometry also gives residents a consistent spatial reference as they move between the street, stairs, and apartments.
Two Frontages Improve Light and Ventilation
With a building footprint of only 84.86 square metres, the plan makes careful use of every available exposure. One side faces the street, while the opposite frontage overlooks a park and a neighbouring daycare center. Openings on both sides support cross ventilation while bringing daylight deeper into the narrow volume.
The park-facing windows frame trees and daily neighbourhood activity, giving the apartments a more open outlook than the compact site might suggest. Instead of directing every unit toward a single urban facade, the design establishes a relationship with both the street and the greener communal edge behind the property.
Calm Interiors Shaped by Changing Daylight
The apartments use restrained white surfaces as a background for trapezoidal wall openings, patterned glass balustrades, and carefully positioned windows. Some of these elements remain visible from outside, allowing the interior rhythm to contribute to the street elevation while maintaining a degree of privacy.
In the maisonette units, gently sloping atriums and openings within the floor slabs introduce filtered daylight between levels. Skylights and windows on both frontages create gradual changes throughout the day, making the compact rooms feel less static. The architecture is therefore experienced through small daily discoveries rather than through a single dramatic interior gesture.
Completed in January 2024, SHIN NAKANO trapezoidal demonstrates how a modest condominium can express a broader urban and geological narrative. Through concrete relief, ventilation, framed views, and carefully modulated light, Ryuichi Sasaki Architecture connects contemporary residential life with the largely unseen landscape of the Musashino Plateau.
| Technical Sheet | |
|---|---|
| Project Name | SHIN NAKANO trapezoidal |
| Building Name | GRANTAGE SHIN NAKANO |
| Location |
4-7-4 Chuo, Nakano-ku, Tokyo, Japan |
| Programme | Residential condominium, 11 units |
| Structure | Reinforced concrete |
| Stories | 5 above ground and 1 basement level |
| Site Area | 152.27 sqm |
| Building Area | 84.86 sqm |
| Total Floor Area | 416.68 sqm |
| Client | Sho Ishihara / Real Partners |
| Lead Architect | Ryuichi Sasaki / Ryuichi Sasaki Architecture |
| Architecture Team | Ryuichi Sasaki, Yuriko Ogura, Anna Osawa |
| Structural Engineer | Tatsumi Terado Structural Studio |
| Lighting Design | Natsuha Kameoka / Lighting Sou |
| Contractor | Magome Construction Company |
| Completion | January 2024 |
| Photography | Takumi Ota Photography |