Environmental-cost framework to investigate impacts of carbon tax policy on material selection for building structures

ABSTRACT Building materials, mainly steel and concrete used in residential buildings, significantly impact CO2-eq emissions. Nowadays, carbon tax policy is used in some countries to reduce carbon emission effects. However, few comprehensive studies have been conducted to investigate the overall impact of such a carbon tax policy on minimizing building CO2-eq emissions. Stakeholders in the building industry often focus on cost criteria to select construction materials, neglecting environmental factors. Providing a cost-emission framework can be beneficial in choosing appropriate materials based on financial and environmental factors. This study proposes a comprehensive framework to analyze the embodied CO2 equivalent emission, carbon taxation, and cost of steel and Reinforced Concrete (RC) structures employing Life Cycle Assessment (LCA) methodology. The framework is implemented on an actual residential building case study to validate its potency. The case study’s results show that the embodied CO2-eq emission of the RC structure is 36% higher than the emission in a similar steel structure leading to 36% more carbon taxation. However, the total material cost of the steel structure is around 65% higher than the RC structure. Thus, carbon taxation policy does not necessarily reduce embodied CO2-eq emissions because stakeholders may prioritize the cost criteria to select building materials.