Circular Economy in Buildings: Service Life Considerations of Paint

Buildings and built environment are responsible for 40% of global CO2 emissions and resulting in climate change and other environmental issues. Life cycle research is a vital tool in understanding and resolving the myriad of multifaceted challenges which have made addressing the status quo complicated. Previous studies show that embodied energy research provides an opportunity to investigate the environmental impact of building materials. However, the emerging field of circular economy has recently presented a platform for a critical appraisal of the association between the lifespan of a material and the potentials for its circularity, as a means of increasing its sustainability. This paper embraces this challenge but further argues that extending the lifespan of a material has quantifiable benefits. The aim of this paper is to explore how the service life considerations of paint as a finishing material in buildings, can help to achieve the goals of circular economy and help reduce the life cycle embodied energy of buildings. The assessment was carried out using an input–output based hybrid approach (IOBHA) to calculate the life cycle embodied energy of the building with a service life of 50 years, and 10 years for the paint. Next, a sensitivity analysis was carried and it was assumed that the MSL was increased by 20% up to 100%, and then the LCEE was recalculated. The findings show that while the LCEE of the paint was 161.8 GJ, increasing the MSL by 80–100% can lead to a drop in the LCEE of the paint by up to 40%. Specific strategies were also recommended to facilitate the extension of the service life and enhance the circularity of paint.