JAILCD2025-033: Systematic Review of Variables of the Embodied Carbon Footprint Assessment in Biological Building Materials

Abstract

In the context of global climate targets, the use of low Embodied Carbon (EC) biomaterials in building construction offers a promising solution by reducing emissions and sequestering carbon. The application of biomaterials in building industry not only realizes carbon emission reduction but also achieves carbon sequestration, while improving transparency in carbon accounting using Life Cycle Assessment (LCA). However, the significant variability exists in how the embodied carbon of these materials is assessed, largely due to methodological inconsistencies. This study conducted a systematic review of existing research on the embodied carbon footprint of key biological building materials such as Mycelium Based Composite (MBC), Hemp Concrete (HC) and Engineered Wood Product (EWP). By establishing a comprehensive framework based on methodological dimensions, namely temporal, procedural and physical, this review aims to standardize the assessment of embodied carbon in biological materials. The methodology involves systematic literature review, qualitative summarization and quantitative investigation about the key variable influencing the EC footprint for biological building materials. Drawing on a meta-analysis of biomaterials in building construction studies published between 2015 and 2024, this study identifies the most significant variables influencing the EC footprint of biomaterials. A normalization process is applied to harmonize discrepancies across studies, enabling valid cross-case comparisons. Key findings reveal that variations in LCA methods, system boundaries, scale of units, functional units, intended use, material composition, fabrication and geographical boundary can lead to substantial differences in reported EC values. The study has provided a theoretical foundation for exploring the relation between the EC of different biomaterials and their variations.