The research aims to investigate and develop component based building skin systems that can be retrofitted on existing buildings and urban fabrics to bring about a change in the environmental response and spatial quality. Evolutionary algorithms to optimize building skin design in a multi-parametric design environment are developed as a part of the system generation. Emergent behavior in building skin is studied, with respect to patterns of solid v/s void, that further lead to the system work-ability and energy efficiency. The investigations leading the research will be based on analysis of the current set of realized and unrealized works in this domain and evaluating them with respect to their dependence on mechanical control and material intelligence. A noticeable gap in this domain lies in articulation of material behavior and embedding it in the system intelligence. Dependency on mechanical control leads to energy inefficiency which can be controlled by developing smarter material systems which can omit the use of mechanical system, partially or completely. A focus will be on increasing the scope of usability of the currently developed materials in this field and their integration at an architectural scale. Another layer of research would focus on creating novel spatial effects, with respect to environmental conditions, to change the identity of the existing fabric by retrofitting of the new system. The system will be tested in multiple climatic models, giving a range of environmental and functional factors, realized under variations in scale.