Complementing emergy evaluation and life cycle assessment for enlightening the environmental benefits of using engineered timber in the building sector

Abstract

Engineered timber can represent a great opportunity to mitigate the large impacts due to the global building sector. However, the most applied environmental assessment methodologies such a life cycle assessment (LCA) might show limited advantages when comparing the impact on climate change of buildings made of traditional materials, such as concrete and steel, and building based on engineered timber. This work proposes emergy evaluation (EME) as a complementary environmental assessment methodology. By expanding the boundaries of the assessment, EME captures input flows and related features, especially in terms of renewability, that are overlooked in LCA. LCA and EME were applied to two identically modeled buildings composed of either only traditional materials or engineered timber as their replacement. EME reveals the higher sustainability level of engineered timber compared to traditional materials in the building sector, capturing larger environmental benefits compared to LCA. Ultimately, the robustness of the results is tested through a comparative sensitivity analysis performed for three geographic scenarios, different energy use scenarios, and different transport distances.