Mitigation measures to contain the environmental impact of urban areas: a bibliographic review moving from the life cycle approach.

The global environmental impact of urban areas has greatly increased over the years, due to the growth of urbanisation and the associated increase in management costs. There are several measures aimed at mitigating this impact that affect in different ways the environmental, economic and societal spheres. This article has analysed a selection of different mitigation measures, related to the built environment, according to the life cycle approach, aimed at identifying the procedural features chosen by the different authors and defining a common way to deal with this issue. In particular, all the individual single steps of a Life Cycle Assessment/Life Cycle Costing of the different studies are analysed and the results of the individual measures are highlighted. The analysis has shown how the scientific literature is mainly focused on the evaluation of the impact of technological solutions related to individual buildings (cool/green roof). Less interest is shown in the solutions for urban areas, while, as far as the impact on greenhouse gas emissions is concerned, some studies are shifting the target to a global scale. Due to the accuracy whereby the calculation of the impact indicators deals with and structures the life cycle methods, opportunities to compare studies developed by different authors are quite rare and hard to find. Hence the need to find a simple, intuitive and flexible scheme to combine some of the most useful results of the bibliographical studies, in a comparative outline of different technological solutions, which can support the decision-making phase through a rough assessment.