Stock- and stress-informed design and fabrication of load-bearing structures from reclaimed timber

Abstract

The structural reuse of reclaimed timber is limited by material heterogeneity, unknown provenance, and the absence of reliable grading procedures. This paper introduces an integrated data-driven design, engineering, and fabrication framework that systematically transforms reclaimed sawn timber planks of heterogeneous quality into high-value structures. The framework establishes a continuous information flow between material characterisation, computational design, structural engineering, and fabrication, enabling reclaimed timber to actively inform every stage of the design and construction process. At its core, a Material Digital Stock (MDS) digitally identifies, characterises, and continuously traces reclaimed timber, serving as the informational backbone through which material-specific data are exchanged across the workflow. Building upon this information, a stock- and stress-informed computational design method negotiates between structural demand and available material stock to generate both the global structural form and the strategic distribution of individual planks. These are realised through a hybrid vertical glue-nail lamination strategy, which combines structural adhesive with hardwood nails to produce continuous engineered timber elements without industrial pressing infrastructure, and are evaluated under serviceability loading conditions using a developed anisotropic finite element model. Material-specific information is maintained throughout mixed reality-assisted fabrication, preserving the link between digital and physical processes and ensuring full material traceability. The laminated structure is transformed into the final architectural form with specific surface features via custom-designed robotic milling procedures. The framework was demonstrated through the design, fabrication, and structural validation of a full-scale single-span research prototype under static loading. The results demonstrate that heterogeneous reclaimed timber can be systematically transformed into structurally feasible laminated systems under serviceability loading, establishing an integrated pathway for high-value structural upcycling and long-term material value retention.

Keywords

Reclaimed timber upcycling / Stock- and stress-informed design / Computational structural optimisation / Glue-nail lamination / Finite element analysis / Structural repurposing

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