Designing for timber circularity: Potential challenges and approaches from the lens of two educational design/build projects

Abstract

To transition to a Circular Economy, architecture schools are incorporating Design for Circularity (DfC) into their curricula. Integrating circularity into full-scale Design/Build prototypes helps students connect sustainable design theory with practice and application of concepts. This paper examines the gap between circular design intentions and real-world barriers, focusing on DfC with wood in two educational projects. The first, in Belgium, follows a “design from reuse” approach using short-length reclaimed sawn-timber to create a small-scale canopy structure. The second, in the USA, adopts a “design for reuse” approach, using plywood to develop a reusable kit-of-parts. In the analyzed cases, the non-standard nature of DfC requires a holistic life-cycle perspective, presenting challenges in material sourcing and quality assessment, significant variability in sizes and condition, and uncertainty regarding mechanical properties. Furthermore, utilizing frequently smaller reclaimed timber elements increases the number of connections, requiring original solutions. These issues complicate architectural design, structural calculation, and permitting and influenced the design and construction in both cases. An analysis of successful DfC cases shows parallels with lessons learned, identifying common barriers and suggesting solutions. Using reclaimed wood for structural purposes requires thorough planning for transportation, storage, regrading, and reprocessing. Design flexibility is critical to accommodate dimensional variability and mechanical downgrading. When designing for reuse, adequate fabrication tolerances and well-designed connections are key to ensuring structural integrity and easy disassembly. Increased educational projects can build a robust knowledge base, leading to currently lacking standardized procedures and streamlining DfC practices in architecture, engineering, and construction industries. This paper enhances understanding of DfC with wood and Design/Build education by identifying barriers, opportunities, and methods to improve education and training, aiming for a more sustainable built environment.