A comparative study of climate adaptive building shells. Design solutions and applicative case studies

The need to cope with climate change effects – particularly those affecting the microclimate of the built environment – as well as the consequences of the energy crisis, is driving designers to prioritize adaptability of building elements as a key feature of new and refurbished constructions. Taking Europe as example, even in the best development scenario, in 2050 it is estimated that heatwaves will occur +19% in frequency than nowadays, and will last +63%; and the annual mean temperature will be +1.6°C. The goal is thus to improve both the energy efficiency of buildings and their ability to react to variable and sometimes extreme external conditions. Within this context, the building envelope plays an essential role to ensure optimal comfort conditions while strongly reducing the building operational energy. Its performances and most appropriate configurations have been extensively studied to provide a well-established set of solutions for the most recurring climate conditions in various world regions. However, the urgency to further increase energy efficiency and the capacity to adapt to a changing climate are pushing designers to explore more low-energy, dynamic, and adjustable building skins. Hence the paper reports an investigation of the theoretical assumptions at the base of climate adaptive building shells and how they influence practical applications in real life solutions. Then, the study considers some innovative solutions and explores the design strategy behind, as well as the deriving savings for different applicative case studies. It also includes a reflection on the choice of dynamism, geometrical configuration, and materials with reference to indoor and outdoor comfort. Alternative design options (which were tested in separate sessions) are compared for each case to discuss the potential and limitations of the devised design methodology.