Building Green, Consuming Embodied Energy? Cradle-to-Gate Embodied Energy Assessment of Green Office Buildings for a Sustainable Built Environment in Sri Lanka

The green building (GB) concept was introduced to reduce the environmental impact of buildings and to achieve a sustainable built environment. Nevertheless, GBs are more focused on reducing operational energy, which has led to the neglect of embodied energy (EE). Thus, as a novelty, this study assessed the construction material-related (cradle-to-gate) EE of green office buildings in Sri Lanka using the Life Cycle Assessment (LCA) methodology. Accordingly, two platinum-rated green office buildings were selected as case studies. The results revealed that the cradle-to-gate EE in Case A is 60,366.38 GJ, and in Case B, it is 21,963.11 GJ. The EE is 6.35 GJ/m2 and 11.68 GJ/m2 for the gross floor area in Case A and Case B, respectively. It was shown that reinforcement steel was the primary EE material, contributing 48.64% of the total EE in Case A and 23.77% of the total EE in Case B. Results highlighted that replacing the high EE materials with the low EE materials can reduce ~43% of the total EE in Case A and ~33% in Case B. This study utilised proxy data from country-specific literature sources and data from ICE, as there was no EE coefficient database available in Sri Lanka. The findings of this study can help construction industry stakeholders reduce EE and related carbon emissions.