Circulation of structural timber for structural purposes: a review of opportunities and challenges

Abstract

The transition to a circular economy is gaining momentum as an alternative to the linear take-make-use-dispose model. Timber-based building materials have received renewed attention due to their role in both natural renewable and technical cycles, offering lower embodied energy than conventional materials, such as concrete, steel or masonry. Moreover, academics and practitioners are investigating methods to implement Design for Circularity strategies to extend material lifespans, reducing the need for virgin resources and minimizing environmental impact. The circulation of structural timber is, therefore, essential to maximize the long-term benefits of grey energy invested in harvesting, transporting and processing timber, as well as its CO2 storage capacity. This study explored key prerequisites for the circulation of structural timber, including production processes, architectural and structural design concepts, dimensioning, and environmental considerations. These fundamentals were examined alongside a comprehensive literature review to identify opportunities, challenges, and critical knowledge gaps. The goal was to support increased and more effective circulation of structural timber in future construction practices.