Double-skin facades (DSF) are gaining prevalence in China. However, the benefits of DSF have not been realized due to the lack of quantitative design verification before construction, and operational challenges. Some building owners have even chosen not to turn on mechanically ventilated DSF. This paper presents a design and operation analysis of the inactive DSF in an office building in China. Its performance was carefully studied with Computational Fluid Dynamics (CFD) and Dynamic Thermal Simulation (DTS). An optimized ventilation rate and annual operation schedule are proposed and the investigation approach is introduced.