The Skyscraper of a New Era with a Huge Void

At the beginning of the twentieth century, modernists in the field of architecture such as Le Corbusier envisioned a future city where the vertical growth of buildings would increase urban density, creating rich parks and public spaces on the ground. However, a century later, the reality of cities shows skyscrapers densely packed together, covering and consuming public spaces.

In 2021, an international competition was held for a 480-meter skyscraper in the North Bund area of Shanghai; sixty architectural firms worldwide submitted proposals. The project called for a mixed-use facility comprised of offices, hotels, retail, and an observation deck, which would serve as a landmark for the area and a hub for Shanghai’s citizens.

Nikken Sekkei drew on its extensive experience with skyscraper design, carefully rethinking the role of public spaces in high-density cities and addressing environmental challenges in our proposal.

【PUBLIC VOID】

Skyscrapers are typically highly enclosed, with the interior and exterior isolated functionally and environmentally. In this proposal, a large opening called the PUBLIC VOID is introduced into the building, creating a diverse series of public spaces that vertically connect the exterior environment to the upper floors.

The total area of the public space created by the PUBLIC VOID is approximately 1.7 times the site area, or 21,000 square meters, in outdoor spaces alone. The skyscraper physically expands the city's public space.

Vertical movement in skyscrapers often involves long, tedious waits for elevators and uncomfortable rides in cramped cabins. To address this, the open-air PUBLIC VOID filled with air and light is connected by escalators, enabling seamless vertical movement from one public space to another. This creates a movement experience akin to enjoying a mountain hike within the city.

This proposal designs a new form of public space made possible by skyscrapers, offering a solution for cities predicted to densify further.

【FORM FINDING】

This distinctive form is the result of meticulously layering design iterations to reduce CO₂ emissions, a major cause of climate change.

By adopting a tapered shape, wind pressure is reduced by 18%, and structural materials are also minimized. Slits and voids are strategically utilized to gently introduce wind and natural light, reducing the need for air conditioning and artificial lighting. Continuous iterations of the form-finding method were carried out with environmental simulations.

Furthermore, the wide-open base of the PUBLIC VOID allows cool air from the river to flow into the surrounding urban space, addressing the urban heat island effect. To maximize this feature, the surrounding landscape was designed integrally with the building.

Overall, the proposal reduces CO₂ emissions over fifty years by approximately 710,000 tons compared to a conventional building—an effect equivalent to creating a 1,620-hectare forest.

【SIMPLE COMPOSITION】
The dynamic PUBLIC VOID space is achieved through a simple, two-axis symmetrical floor plan and a clear structural system that connects two L-shaped buildings at intervals of 50 or 150 meters in height. By avoiding complexity and adopting a rational structure, the PUBLIC VOID is designed as a prototype that can be applied to other skyscraper projects in the future.
The series of large openings and three-dimensional public spaces emerge as a landmark in Shanghai's urban landscape while simultaneously addressing urban environmental challenges. This URBAN VOID MOUNTAIN is the prototype for a new era of skyscrapers.

Among 60 architectural firms worldwide that submitted proposals, Nikken Sekkei's design, while not selected as the winner, earned significant support from expert jurors.

Project name: Shanghai 480m tower international competition Proposal “URBAN VOID MOUNTAIN”
Purpose: Office, Hotel, Retail
Site area: 12,733 sqm
Total floor area: 429,223 sqm
Number of floors: +95
Eave height/maximum height: 480 m
Main structure: SRC+RC+S

Client name: Shanghai Industrial Development Co., Ltd., Shanghai Chengtou, Shanghai Construction Group Co., Ltd. Consortium

(Competition agent) Shanghai International Tendering Co., Ltd.
Lead architect: NIKKEN SEKKEI LTD
Main scope: Competition
Image credit: NIKKEN SEKKEI LTD