Comparative Assessment of Embodied Energy, Carbon Emissions and Environmental Impacts of Conventional and Sustainable Construction Materials

This paper developed a harmonized, ISO 14040/14044-consistent comparative framework for five conventional-versus-sustainable construction-material pairs, using only traceable literature- and database-derived coefficients, and propagated the documented reduction ranges through Monte Carlo and sensitivity analysis rather than reporting single point estimates. Embodied-carbon reductions of 8–82% were found across the five categories, with a composite high-substitution (S3) scenario mean reduction of 47.7% (5th–95th percentile: 39.0–56.2%). Recycled steel offered the largest and most certain benefit; geopolymer binder and mass-timber structural frames offered substantial but considerably more uncertain benefits, with documented cases in which a conventional material matched or outperformed its “sustainable” counterpart. A break-even transport-distance calculation demonstrated that production-stage carbon advantages can be eroded by long-distance sourcing, providing a simple, generalizable check for practitioners. The central conclusion is that methodological harmonization — consistent functional units, system boundaries, and explicit uncertainty reporting — is at least as important as material selection itself in producing defensible, comparable construction-material LCA results, and that several of the inputs needed to convert this framework into a complete, primary-data Q1-level LCA (Section 7) remain to be collected rather than assumed.

Barbhuiya, S., & Das, B. B. (2023). Life cycle assessment of construction materials: Methodologies, applications and future directions for sustainable decision-making. Case Studies in Construction Materials, 19, e02326. https://doi.org/10.1016/j.cscm.2023.e02326 Central Electricity Authority, Government of India, Ministry of Power. (2024). CO2 Baseline Database for the Indian Power Sector, Version 20.0. Circular Ecology. (2019). Inventory of Carbon and Energy (ICE) Database, Version 3.0. University of Bath / Circular Ecology. Cong, P., Du, R., Gao, H., & Chen, Z. (2024). Comparison and assessment of carbon dioxide emissions between alkali-activated materials and OPC cement concrete. Journal of Traffic and Transportation Engineering (English Edition), 11(5), 918–938. https://doi.org/10.1016/j.jtte.2023.07.011 Ding, T., Xiao, J., & Tam, V. W. Y. (2016). A closed-loop life cycle assessment of recycled aggregate concrete utilization in China. Waste Management, 56, 367–375. https://doi.org/10.1016/j.wasman.2016.05.031 Hammond, G. P., & Jones, C. I. (2019). Inventory of Carbon & Energy (ICE) Database (Version 3.0). University of Bath. Hemmati, M., Messadi, T., Gu, H., Seddelmeyer, J., & Hemmati, M. (2024). Comparison of embodied carbon footprint of a mass timber building structure with a steel equivalent. Buildings, 14(5), 1276. Hossain, M. U., Poon, C. S., Lo, I. M. C., & Cheng, J. C. P. (2016). Comparative environmental evaluation of aggregate production from recycled waste materials and virgin sources by LCA. Resources, Conservation and Recycling, 109, 67–77. https://doi.org/10.1016/j.resconrec.2016.02.009 International Organization for Standardization. (2006). ISO 14040:2006 — Environmental management — Life cycle assessment — Principles and framework. ISO, Geneva.