Embodied Water in the building life cycle: current research and future directions

Water, recognised as a scarce resource, has been considered for sustainable development goals (SDG-6) and acknowledged 2018–2028 as the water action decade. Water is essential for the construction industry, and it consumes around 15–16 % of the global freshwater. While water is directly utilised for construction, for instance, in preparation of mortar, an enormous quantity of water is indirectly consumed through building materials, energy sources, etc. The combination of direct and indirect water components is termed Embodied Water (EW). Minimising EW throughout the building life cycle is imperative to drive towards sustainable development. However, EW has not yet received its due recognition as an essential element in evaluating the sustainability of the building life cycle, with limited research studies addressing its significance. Thus, this paper aims to analyse the contemporary status, barriers, strategies, research trends, and future directions of EW within the building life cycle. The systematic literature review approach was adopted to attain the aim of this paper. The results of this study reveal twenty-two barriers hindering the reduction of EW and twenty-eight strategies to overcome them. Frequent usage of high water-consuming materials, water and material wastage, and difficulties in estimating EW are some of the main barriers identified in this study. Selecting materials with low EW, effective and efficient usage of materials and machinery, and introducing water management-related policies are some of the key strategies derived from this research. Additionally, this paper presents nine research trends and fifteen prospective research avenues identified through existing studies.