Curved insulated glass units formed by tempered bending or annealed slumped bending offer a bold expression of architectural design with transparency and energy efficiency. As more skins with complex geometry are built, design teams need to engage consultants and international industry experts to define the properties and constraints of curved insulated glass units in line with relevant standards and performance. This paper explores the traditional manufacturing capabilities, processes, and further investigates the advantages and structural performance of these glass products. The stiffness gained from curvature in fact presents an opportunity to decrease the visual mass of mullions along straight edges. Thoughtful consideration is also given to address redistributed forces, buckling, and increased effects of climatic loads on a sealed interspace with flexible boundaries. The structural performance and design requirements are compared for insulated glass units with flat, shallow and tight curvature using a comprehensive glass, air, and silicone finite element model. Based on this study, suggestions for specification and analysis of curved insulated glass units is provided.