Chengdu, China

Invited International Competition 2009 - 1st Prize

Completed 2017

Client: Chengdu High-Tech Investment Group

Project area: 103,650 m² (above ground), total project ca 160,000 m²

Icon Yunduan Tower is a 192-metre-high hybrid building located in a high-tech zone on the outskirts of the city of Chengdu, China. The aim of the project was to create a landmark visible on entering the city as well as a focal point for the earlier building phases of the area. The project is based on a winning entry in an invited architecture competition in 2009.

The assignment comprised the design of an office and residential area, which was developed further in collaboration with the client and a local design office, China Southwest Architectural Design & Research Institute (CSWADI). Due to the scale and tight schedule of the project, PES-Architects proposed that the residential building be designed by the other Finnish competitor, Helin & Co Architects.

During the design process, what was originally planned as an office tower evolved into a versatile, mixed-use building complex. A shopping centre occupies the first two levels of the 47-storey building, while the third and fourth floors feature restaurants. A conference centre spans the fifth floor, followed by 23 floors of offices and 13 floors reserved for an apartment hotel. The top three floors contain dining, reception and meeting areas. The roof features a helipad.

Underground premises provide parking for 3,000 cars and a connection to the metro station. The underground spaces were originally planned to accommodate a spa and gym, but the client later decided to replace these with a concert hall seating 900. This was designed by CSWADI partly under and partly adjacent to the building.

The tower has an L-shaped plan at ground level that grows into a square towards the top. This form creates a sweeping façade that overlooks the Tianfu River and a straight edge that defines the corner of the site along Tianfu Avenue. The curved elevations to the south and east are defined by green terraces up to the 30th floor. Glass and glazed ceramic elements form a checquered pattern on the other facades.

The concrete-braced core of the building comprises the shafts and vertical connections, while the rest of the building frame is of steel. The main components of the frame consist of round, concrete-filled steel columns and a 9 m x 9 m grid formed of 600 mm x 110 mm steel beams. A 120 mm thick concrete slab is cast over the secondary beam structure of the grid. This basic structure is applied throughout the building in different ways.

PES-Architect also created the master plan and concept-level landscaping plans for the site. The draft designs also included detailed interior design plans for all the building’s public spaces; these were subsequently adapted to local preferences and the tenants’ requirements.

The main tenant of the building is the European Union, which plans to use it as a base for European organisations and companies in Western China.

The form of the building is evocative of a white mountain with garden terraces, rising from the water up towards the sky. Hence, the building was named Yun Duan, “Above the clouds”.