The myth of informed decision-making: explaining the substantive effectiveness of LCA use in a building product development project

Abstract Purpose This study aims to better understand the substantive effectiveness of life cycle assessment (LCA) in practical settings. While LCA has aspired to inform decision-making for decades, it is clear that many good LCA studies are not followed by tangible reductions in product environmental impacts. This raises the question whether the underlying model of LCA use does justice to the practical reality of decision processes in projects and organisations. Methods An ethnographic study of a building product development project has been conducted, with a special focus on its use of LCA. Rather than assuming that LCA results lead to more sustainable decisions, actual events have been analysed where LCA influenced the development project over a period of 3 years. The data come from interviews (32), first-hand observations (18 days), and project documentation (> 100 documents), including five LCA studies. The analytic process followed an empirically grounded research approach, leading to a detailed process-based description of LCA use in the development project and an analysis of the substantive effects of each LCA study. Results and discussion Studying a single case in detail enabled the identification of effects from LCA use that normally remain invisible. The analysis revealed that the use of LCA in the development project deviated from common expectations. Rather than a straightforward causal relationship between a commissioned LCA study and a specific design decision, LCA use followed a complex sequence of events, including a diverse set of LCA studies, activities, and project outcomes. Together, six deviations from the conventional model of LCA use were identified: (1) multiplicity, (2) partial effects, (3) displaced effects, (4) activity-based effects, (5) heterogeneous actors and activities, and (6) a two-way directionality of effects. These effect types have been grouped into knowledge- and activity-based models of LCA use. Conclusions Viewing LCA use as informed decision-making does injustice to the manifold ways in which LCA leads to substantive effects in the studied development project. Relying solely on the conventional linear model is likely to disappoint as it guides LCA practices toward producing accurate information efficiently, rather than focusing on the substantive actions, events, and mechanisms that reduce product environmental impacts. Recognising these limitations, practitioners are recommended to consider a wider spectrum of effect mechanisms by drawing on the proposed knowledge- and activity-based models of LCA use. Given the importance of reducing product environmental impacts, more research is needed to understand the substantive effects of LCA.