Speaker
Description
The decarbonisation of building envelopes requires multifunctional façade components that integrate indoor comfort with low embodied environmental impacts. Acoustic Metamaterial Windows (AMWs) are an emerging façade solution capable of providing passive noise attenuation while preserving natural ventilation, yet their material sustainability has rarely been quantified. This paper presents a cradle-to-gate Life Cycle Assessment (LCA) of an AMW prototype produced through hybrid digital manufacturing, combining additive manufacturing of polylactic acid (PLA) metamaterial units with laser-cut polymethyl methacrylate (PMMA) panels. The assessment follows ISO 14040/44 standards and applies the ReCiPe Midpoint method to evaluate climate change, resource depletion, and toxicity indicators. Results demonstrate that PLA 3D printing dominates Global Warming Potential due to filament production and electricity demand, while PMMA panels significantly affect climate-related and ecotoxicity indicators. Circular material strategies yield measurable benefits: replacing virgin PLA with 20% recycled PLA reduces GWP by 6.6%, and substituting PMMA with flat glazing further lowers impacts across most categories. Comparative benchmarking against Environmental Product Declarations of conventional window systems shows that optimised bio-based AMWs can achieve embodied emissions comparable to PVC and recycled aluminium frames. Beyond quantitative results, the study proposes a transferable LCA framework for early-stage metamaterial components supporting evidence-based sustainable material selection decisions.