C41 -- Life Cycle Emissions of Walling Systems in the Housing Sector of India

Globally, the building sector is a significant source of carbon dioxide (CO₂) and other greenhouse gas (GHG) emissions, and it is anticipated that the building stock will double by 2060. The latest assessment report from the Intergovernmental Panel on Climate Change for the Mitigation Working Group (AR6 WGIII) highlights that the buildings and construction industry offers significant global mitigation potential for reaching the Paris Agreement. In India, the building sector accounts for around one-fifth of total CO₂ emissions and nearly 33% of the nation’s energy use. Rapid urbanization has spurred the demand for housing in India, resulting in an 11.1% rise in residential building construction over the last eight years. The current policy landscape and practices are mostly aligned in addressing operational carbon with a limited focus on the life cycle approach covering embodied carbon. In the case of the residential sector, operational emissions account for 60-70% of the overall emissions, while embodied emissions make up the remaining 40% over a building's entire lifespan. In the next 20 years, India’s total building space is projected to be more than double, signalling huge opportunities to reduce embodied emissions from the whole life cycle of building materials or other products. Given the projection of a significant volume of new construction, it is worth noting that upfront carbon emissions will contribute more to the entire carbon footprint of the building through its long life. This study is directed towards the embodied carbon assessment of industrially manufactured walling systems, that are identified as a substitute for conventional systems to meet the housing demand in India. These systems provide quick construction time and are economically affordable. ISO 14044 formalizes the requirements for conducting Life Cycle Assessments. Preliminary work revealed the absence of databases for Indian materials and products; thus it is necessary to adopt a robust framework that deals with sensitivity and uncertainty analysis of the results. The functional unit considered is a square meter of a typical dwelling unit for 50 years. The results show that the overall embodied emissions of the emerging walling systems are 12-49 % higher while the operational emissions are 1.5-3% lower compared to conventional systems.