The moldable formwork and the special spatial shell express the flexible strategy of the building when it responds to unknown changes, and respond to the social and urban issues in the area. As a temporary installation, foamed polyurethane and nylon rope nets are used as the main materials of the roofing system. After the rope nets are tensioned by hanging weights, polyurethane is sprayed to complete the pre-stressed shell. This construction strategy has dealt with structural uncertainties, and at the same time, it has obtained good mechanical properties, making it possible to simplify construction. The arrangement of the columns is determined by optimization of the force, in order to achieve the largest overhanging distance and the smallest thin column effect.