A Higher Purpose: Civic Spaces in Tall Buildings

As we consider how major cities have developed over the last few decades, the rush to build supertall towers seems to have come and gone. A spike in the construction of 400 meter–plus towers in cities across China, the U.S., and the Middle East took place during a particular span of time when growing cities wanted extraordinary buildings to serve as landmarks that signified innovation and growth. Lately, though, the need for these projects has slowed down due in part to the economic and mechanical challenges that come with constructing and finding tenants for these unique projects.

Note

This story is adapted from a presentation given by President and Design Principal James von Klemperer at the 2023 CTBUH Annual Conference in Singapore.

In China, where the profusion of skyscraper construction was especially intense, a partial ban on supertall towers reflects how cities’ priorities are changing. The country’s National Development and Reform Commission and Ministry of Housing and Urban-Rural Development forbade the construction of skyscrapers higher than 150 meters in cities with less than three million inhabitants, while banning those higher than 250 meters nationwide, unless they serve a higher purpose. For context, the US has only two cities with populations over three million, while China has 38 (as of 2024).

To design tall buildings that serve the present-day needs of Chinese cities, it is helpful to look at the spatial relationships that defined these cities historically.  A 20-foot-long scroll from China’s Song Dynasty shows a town’s happenings during the Qingming Festival, organized horizontally along a river. The image depicts civic qualities such as the importance of connection between communities, access to nature, defense systems and regulated entry, and general social life and trade patterns.

A segment of the 20-foot long scroll.

­­KPF’s goal in the design of its supertalls is to transfer this system to the vertical format, effectively utilizing space in a dense location while providing users with a full range of amenities. As designers of 4 of the 10 tallest towers in the world, KPF is no stranger to supertall design, and the firm’s work in this sector has continued thanks to one defining factor: Our towers engage their communities through the inclusion of civic spaces.

Four KPF-designed buildings are among the world’s tallest.

Early supertall structures served an important purpose in their cities, often anchoring the urban plan and acting as a larger catalyst for the district. Current supertalls are still anchoring structures and skyline landmarks, but they need to serve their cities in new ways. The first example of how KPF is approaching this topic is in Chengdu.

The heights of Chengdu Tianfu Supertall (left) and North Bund (Lot 91) (right).

Chengdu Tianfu Supertall

The capital of Sichuan province, Chengdu has evolved and expanded since its early founding. The center has shifted south from the old city center of the 4th century B.C., with a new center now emerging in Tianfu.

Move the center divider to see the shift in Chengdu’s city center.

This is the site of the Chengdu Tianfu Supertall, previously referred to as Panda Tower due to the project’s location, with the Sichuan Province as the home to the largest percentage of Giant Panda. Chengdu also established multiple nature reserves and a dedicated facility, Chengdu Research Base of Giant Panda Breeding. The supertall is comprised primarily of office programming and its two neighboring buildings of hospitality and residential units. These shorter buildings serve as stepping structures to help mediate the tower’s height.

The form of the supertall is inspired by the towering rock formations of Zhangjiajie National Forest Park, referencing Chengdu’s position as a gateway to the mountains, and the façade features a vertical striation texture like that of the mountains.

Zhangjiajie National Forest Park (left, credit: aphotostory/Adobe Stock) and an early concept sketch of Chengdu Tianfu Supertall and the neighboring structures in the complex (right).
The concept of the tower is depicted in this early sketch, where green spaces are easily accessible, with sky gardens acting as a vertical promenade that leads to the top of the tower.

The base of the tower is activated by a retail street with layered levels to mirror the historical pathways of the city. The tower’s civic programming begins at the ground level, with a design inspired by the Du Fu Thatched Cottage’s arched bows and bamboo, elements that are referenced in the lobby’s ceiling form and materials. At multiple locations throughout the building, dedicated spaces evoke aspects of Chengdu, encouraging the users to interact with their surroundings.

The ground floor lobby.

At the first sky lobby, the design team looked to the People’s Park in Chengdu, creating a space where visitors can rest and have refreshments. The pond formation is a clear reference to the park’s central lake, and the prominent inclusion of stone is a heavy nod to the outdoor park. Almost midway up the tower, the atrium is inspired by the Heming Tea Garden, where people can socialize and experience the blurred barrier between indoors and outdoors. The WuHou Shrine Temple is the inspiration of the communal space in the upper half of the tower, with stone pillars and hanging plants.

Moving up the tower’s sky lobbies and the accompanying inspiration, from left to right:: the People’s Park (credit: LP2 Studio/Shutterstock); the Heming Tea Garden (credit: LP2 Studio/Shutterstock); and the WuHou Shrine Temple (credit: ClemV/Shutterstock).

At the crown, the space extends beyond a gathering location, transforming into an experience in the clouds. The interiors take inspiration from the Shudao Mountain Path, a snaking bridge that works its way through the mountains. A series of pathways in the tower’s observation deck and gathering area invite visitors to view the city below from all angles. These paths culminate at the very top of the crown, where an event space offers a variety of uses and a ceiling height of 25 meters.

An overview shot of the tower at sunset (left) and a close up of the crown space (right).

North Bund (Lot 91)

Located in North Bund, the newest emerging commercial center in Shanghai and the third point in a triangle of the city’s business districts, North Bund (Lot 91) will be Shanghai’s first all-electric tower and the world’s tallest upon completion. The tower’s form starts as a circle at its base, transforming to a triangle at the crown. Each apex of the stacked shapes relates to the neighboring business districts, acting as a gesture to the city’s growth and success.

The three districts form a triangle of innovation (left) and the North Bund (Lot 91) as seen from the Huangpu River (right, credit: SAN).

The team uses an analogy of a core sample to explain the building. In the sample, you can see different materials that showcase different eras. The tower provides a similar understanding from the exterior through the evolving shape and how it relates to the programs. At the base, the floorplates have an expansive depth and are best suited for coworking spaces. Midway up, the floors have a slightly smaller depth and are home to a typical office tenant. At the top, a hotel occupies the upper floors where there are medium depth floor plates.

North Bund (Lot 91) is one of only a few supertalls to be 100% triple glazed (KPF’s CITIC Tower was the world’s first). By being all electric, the building will be carbon neutral as the city’s power grid transitions to renewable energy. The tower was designed as a vertical sponge city with rainwater storage and a sloped roof design to direct water to a single collection point. The triangular structure reduces embodied carbon, as it requires 15% less concrete than a typical extruded tower.

With proximity to three rivers, the tower’s sweeping façade references the fluid movement of water. This feature is prominent at the base, as the form lifts to present the entrance. This movement is continued inside the building in the lobby’s curves and cutouts.

The building’s base is designed to invite the public in, offering easy access to a system of pedestrian pathways connecting the project with the district.

Moving up from the base, an elevated bridge guides people around the building, continuing the notion of upward exploration, leading to the multiple sky lobbies with social and business spaces, and culminating at the crown’s public space, notable for its sweeping arched structure and views of the city. Designed as an elevated town square, the column-free space is suited for a variety of functions and events, from performances to speeches and celebrations.

Moving up the tower from left to right: the podium public space, a biophilic sky lobby, and crown event space.

The most visible contribution of supertalls is their significance to city skylines, serving as icons of growth and success. What the Chengdu Tianfu Supertall and North Bund (Lot 91) achieve is success beyond their visibility, serving as gathering places for locals and visitors alike to experience the city from a new height. Both projects differentiate themselves from their peers through their commitment to the public, earning their position as supertalls with a higher purpose.

Chengdu Tianfu Supertall (left) and North Bund (Lot 91) (right). Credit: Atchain.