Harajuku Square | Nikken Sekkei

NIKKEN SEKKEI (architect)＋ Akihisa Hirata Architecture Office (facade and rooftop designer) 

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A building for the fashion and art mecca, Harajuku

Situated on the corner (“Kado” in Japanese) of Meiji-dori and Omotesando Avenues amidst the international tourist destination of Harajuku, Harajuku Square (Tokyu Plaza Harajuku ‘Harakado’) was granted redevelopment planning permission in 2016 and took on the objective to establish a commercial hub befitting the location. A safe pedestrian network was created by road expansion, eliminating a five-way junction, and developing multi-level green spaces. 

Under the long influence of Western culture, this district – a birthplace of numerous renowned fashion brands and creators – needed a space for a variety of energetic entities to coexist and stimulate each other. There also was a goal to enrich the intersection by greenery harmonizing with the Meiji Shrine forest, the Zelkova tree allee of Omotesando Avenue and the rooftop garden of Tokyu Plaza Omotesando ‘Omokado’ located diagonally across.

To achieve these goals, a high-density building framework was established by consolidating the site and by using the rules of the District for Intensive Land Use system and floor area ratio exemption for mechanical facilities such as the subway. By carving out the corner volume and creating a rooftop garden that opens to the intersection, we proposed a building with ground-level greenery extending vertically upward to the roof. Subsequently, in collaboration with Akihisa Hirata Architecture Office (selected via design competition), we proposed a glass facade with the concept of "KNIT DESIGN” (Weaving a city) and a rooftop garden acting as a plaza for the city.

Realizing a highly complex, multi-faceted glass facade

The glass facade is composed of ‘Umi’ (Japanese for “sea”) – a surface with water-like undulations – and ‘Shima’ (Japanese for “island”) – a flat surface with the view of the interior. The aim was to mirror the cityscape and passersby on the highly reflective glass and create a new landscape for this intersection.

The design team believed the frameless SSG curtainwall system was essential for this facade design, where the reflected images were to stand out more than the building itself. The four-sided SSG construction method had few precedents in Japan at the time, so we drew on the latest domestic and international knowledge and techniques. The polygonal glass, appearing irregular at first glance, is defined by a regular 2,100 mm wide module. Construction efficiency was further ensured by limiting the projection dimensions to three types: ±0, +225 mm and -225 mm. To emphasize the sense of depth within this limited range, we strategically selected three types of heat-reflective coatings and back panels and achieved the iconic refracted surfaces.

The aluminum frame incorporates a hinge-type mechanism for stepless angle adjustment, enabling the precise support of complex glass surfaces that tilt in multiple directions. During construction, in addition to calculated analyses and design reviews on paper, numerous full-scale performance and component tests were conducted by curtainwall manufacturers and general contractors to ensure construction quality. Management systems and quality control processes were monitored via documentation, while product control was assured by trial installations and post-disassembly inspections. The design team, engineers, and construction team worked together as one to tackle the complex challenges in realizing this sculptural and dynamic facade. 

Integration of Interior Planning, Structure and MEP Systems

In addition to the challenging exterior, the floor plan was developed in consideration of various complex disciplines.

The building framework is designed to accommodate a mix of uses – commercial retail from the basement to middle floors, exhibitions on the fourth floor, and dining on fifth and sixth floors – all within the site footprint shared with the existing Tokyo Metro facilities. The retail layout consists of units with various scales and specifications, expecting a wide range of tenants, from large luxury brands to counter-only food stands as small as 3 sq m. Some units are equipped with storefront facades which tenants may alter, and some are readily finished and operable by mere transfer of merchandise and furniture. Foreseeing frequent interior alterations, pre-defined rules for evacuation safety were set up, so that renovations within such set parameters are allowed without reapplying for a new evacuation certification.

The structural design closely assessed the existing subway structure and utilized its framework to support the load of the new extension, reducing the size and cost of structural members. Mechanical and electrical design strategically employs a cubicle-style layout on each retail level to avoid crowding by centralized wiring and providing space for future power capacity upgrades.

The retail corridor is designed with a skeletal grid ceiling as homage to the former Central Apartment (completed in 1958 and demolished in 1998), which once housed many creators and a hub for Harajuku culture. This street-like design makes service routes easily visible and facilitates future renovations. Through the integration of architecture, structure and MEP strategies, high levels of design and performance were achieved. 

Creating a rich public space via a rooftop garden

While the ‘Omokado’ building, sitting diagonally across ‘Harakado’, features an enclosed rooftop garden, Harakado’s roof is sculpted with greenery and a grand staircase that open towards the Jingumae intersection. Harakado’s planting scheme, which was proposed with the concept of ‘New Nature’, features not only native species but also climate-resilient plants such as palm trees. Together, the surrounding and seating areas create a variety of places to gather and relax, forming a gracious public space. From the rooftop, visitors may enjoy views across the intersection, creating a unique opportunity to engage with the city at an elevated level through photography, event viewing, and observing urban life. Since its opening, ‘Harakado’ has collaborated with tenants, local businesses and community organizations to host a variety of events that activate connections across the intersection and throughout the district. Through these initiatives, ‘Harakado’ seeks to contribute to the vitality of the neighborhood as a whole.

Aiming for a new type of commercial facility and a “hub” for cultural expression

Since its opening in 2024, ‘Harakado’ has been home to a variety of tenants – from a design school, photography studios, and a co-creation space to a public bathhouse. The interiors and layouts are constantly being adapted to accommodate diverse tenants and events. The public area planned throughout the building, both inside and out, welcomes visitors of all nationalities, ages and genders – offering a space with the enduring value of an urban oasis. We hope that ‘Harakado’ will become a new kind of commercial facility that goes beyond mere consumption by fostering new encounters and stimulating creative and cultural expression.

Building name: HARAJUKU SQUARE (TOKYU PLAZA HARAJUKU ‘HARAKADO’)
Project name: Jingumae 6 Urban Redevelopment Project
Primary use: Commercial building
Location: Shibuya ward, Tokyo, Japan
Site area: 3084.54 smq
Total floor area: 19,893.74 smq
Number of floors: Three basement levels, nine above ground stories, one penthouse level.
Eave height / maximum height: 46.40 m
Main structure: Steel/Reinforced Concrete/Steel-Reinforced Concrete
Completion: August 2023

Client name: Jinroku Redevelopment Co., Ltd.
Lead architect: NIKKEN SEKKEI
Exterior and Rooftop design: Akihisa Hirata Architecture Office
Commercial interior design: NOMURA
Design management: NIKKEN SEKKEI / MAIO Architects
Landscape design: DAISHIZEN
Main scope: Design and Supervision
Construction Contractor: Shimizu Corporation
Other collaborating design companies:
Lighting: Izumi Okayasu Lighting Design Office
Photo credit 1: SS Co., Ltd.
Photo credit 2: Kenya Chiba