Exergy-Based Responsive Building Composites For Thermal Control Stimuli of an Adaptive Envelope 

The paper presents and discusses new methods to identify, understand, develop and test novel timber composites for exergy-based adaptive behavior. The aim of the paper is the development of new design integrated methods for the implementation of active responsive materials in architecture and construction, focused on application for intrinsic thermal responsive and adaptive architectural surfaces. Through material-driven and computational studies, the paper presents a material design survey across three groups of responsive timber composites – single-veneer elements, bi-layers and functionally graded materials (FGM) - and a systematic comparative review of their dynamic thermal responsive and structural performance, in relation to operative temperature regulation. Based on the first studies, an oak responsive specimen is developed and further tested towards implementation, as part of an adaptive envelope demonstrator. The research findings suggest that the coordination between geometric arrangement, material layout, hierarchy and binding techniques between the different oak layers leads to the development of a wider range of behavioral system outputs and allow for high resolution steering of the exergy-based responsive timber composites performance in an architectural scale. Finally, the paper speculates on future fabrication strategies and architectural applications of multi-material composites that could introduce new hybrid properties in the responsive architectural system.