Quantification process of carbon emissions in the construction industry

Abstract

Climate change has raised awareness on the need to achieve net-zero carbon emissions and improve the sustainability of buildings. To reduce the complexity of quantifying carbon emissions, there is a need for practical guidance on the quantification of lifecycle carbon emissions from buildings. Existing reviews appear to only focus on part of carbon emissions quantification and are therefore deemed unable to provide an overview of how to quantify the building's whole lifecycle carbon emissions. Hence, this study aims to review the quantification process of carbon emissions from cradle to cradle in the construction industry, which included trends in the materials studied, lifecycle stages studied, quantification methods, common data extraction practises, assumptions made and formulas used to quantify carbon emissions. A systematic review was conducted according to the PRISMA methodology. This study identified 699 publications from Scopus and Web of Science, and 65 full-text articles were included in the review. It can be concluded that the current practises lack transparency, which prohibits the comparison of different case studies. Also, all the information required for the quantification of carbon emissions during different stages was specified in detail to guide the carbon quantification process. The review further found that the production stage was the most commonly studied stage in previous research. In cases of missing information, assumptions were made, which were found to be common in practise. The underlying assumptions must be explicitly and thoroughly specified in order to avoid simplification and prevent inaccurate quantification of carbon emissions, and ultimately ensure the effectiveness of low-carbon design strategies. The review also highlighted the challenges in quantifying carbon emissions and proposed that these challenges be addressed by identifying appropriate solutions through the integrated use of digital technologies, such as Building Information Modelling (BIM), the Internet of Things (IOT), and blockchain technology. Adoption of these technologies can lead to better data collection and sharing, increased transparency, secure collaboration among stakeholders, and the potential establishment of standardised methodologies for accurate carbon emissions quantification, all of which can lead to improved energy efficiency management in the built environment.