What is portal carrier

Bird’s Nest Olympic Stadium, Beijing, China

46,000 square meters

single-layer ETFE film


individual foil fields with a size of up to 216 square meters


Stainless steel ropes to support the ETFE foils

bird’s nest olympic stadium - made of 46,000 square meters of single-layer ETFE film

The national stadium in Beijing, unofficially called "Bird’s Nest", is considered a logistical and technical-craftsmanship masterpiece. The powerful and dynamic mesh of shiny silver steel supports and membrane fields running in different directions forms a unique sports facility, designed by the architects Herzog & de Meuron. The stadium consists of two structurally separate parts: the braided steel structure and the internal concrete boiler with stands. The primary construction of the steel structure consists of 24 portal beams welded together to form a unit. The secondary structure of irregularly arranged supports and struts, which serve for stiffening, supports this construction.


    The open lattice structure was given a translucent membrane to provide horizontal protection from the weather. This single-layer ETFE membrane with a thickness of 250 µm is printed with a silver-gray dot grid in order to reduce the incidence of light. The total membrane area of ​​38,000 square meters is made up of 880 individual foil fields that are up to 216 square meters in size. Due to their large spans, they are supported by 4,690 stainless steel cables. Since the tolerances of the steel construction were difficult to calculate in advance, the foils were only made to measure. This resulted in its own 3D geometry for each individual field, which was determined with the aid of a computer. Each membrane field is attached to wide steel drainage channels with aluminum clamping profiles.

    An interior membrane made of PTFE-coated glass fiber fabric prevents a view of the roof structure and also improves the acoustics. The installation time for the roof covering was 40 weeks.

    Header image: © Margita Jocham

Construction board

Builder National Stadium Co., Ltd. Beijing (CHN)
General contractor Beijing Urban Construction Group
architect Herzog & de Meuron
completion 2008
Performance from seele
  • Total membrane area: 38,000 square meters
  • Single-layer ETFE, film thickness 250μm
  • 4,690 stainless steel ropes