Decision-making tool for the assessment and selection of construction processes based on environmental criteria: Application to precast and cast-in-situ alternatives

•The model quantifies the usually ignored cradle-to-gate impact of construction work.•It is a useful tool for comparing alternatives in terms of environmental impact.•It can be applied at both pre-construction and construction stages.•It can be applied to different types of infrastructure and building projects.•It can help decision makers, public administration, design & construction companies. This paper presents a quantitative environmental impact assessment tool for the decision making of construction processes including structures, infrastructures and buildings by means of an Environmental Impact Index (EII) to be applied at design and/or construction stages. The research is based on multi-attribute utility theory, interviews with experts representatives of the different stakeholders in construction, and an analysis of fifty-nine European and Spanish environmental legislative acts. The resulting tool was applied to two construction alternatives for road drains (one precast and one cast-in-place). The findings show that the tool enables the prioritisation of construction processes and the selection of the best alternative in terms of environmental impact and that the results are stable to reasonable weight variations. The tool contributes to decision making in the context of project management in construction: it can help professionals in public administration, and design and construction companies. It helps to quantify the cradle-to-gate impact of construction work, which has usually been less studied than the operational impact in the life-cycle assessment of buildings. The tool is being piloted in construction projects of the Barcelona City Council.