Bird's Nest Ⅳ

The eastern and western stands of Beijing National Stadium are higher than northern and southern stands, in order to provide better view for spectators. Pipes placed under the playing surface gather heat in the winter to warm the stadium and coldness in the summer to cool the stadium. While the rain is to be collected for rainwater recuperation, the sunlight is to filter through the translucent roof, allowing the lawn to get essential ultraviolet radiation. On the facade, the inflated cushions are mounted on the inside of the structure where necessary, e.g. to provide wind protection. All the facilities that can bring much convenience have been taken into the design of such a huge project. It is a self-contained unit including the restaurants, shops, restrooms, suites etc.