This study provides LCA reference benchmarks for residential buildings in Northern Italy and Denmark. Furthermore, the benchmark derivation process is analysed to highlight the trade-offs that relate to the methodological choices made by benchmark developers, considering the objectives of the stakeholders. Reference benchmarks for the two contexts are calculated based on national samples of residential buildings. A comparative analysis pinpoints the methodological factors regarding system boundaries, inventory requirements and databases that, from a calculation aspect, affect the benchmarks. Results thus highlight the uniqueness of each benchmarking system put into practice, and emphasize the need for clear calculation rules and transparency within each benchmark system. The identified trade-offs from the derivation process furthermore indicate the inherent need to balance the different interests relating to the stakeholders’ roles when applying the benchmark. The mapping of different trade-offs presented in this study provides benchmark stakeholders with an overview that allows for open discussion about which priorities and choices will fit a specific context of benchmark application.

Enabling Technologies have the potential to transform both the physical flow of materials and resources (production and construction methods), and the intangible organisational and managerial relationships (exchange and monitoring of data and relationships along the entire chain of value). They should, therefore, be considered important in supporting change processes aimed at the circular use of resources. This paper presents some research and experiments, at European and Italian level, aimed at developing and applying Enabling Technologies for circular economy, and at aligning them with the needs and challenges of society, by directly involving actors of the building sector ecosystem in moments of discussion and co-creation to define potential strategies and operational actions for innovation in the sector.

The application of sustainability assessment in a decision context is associated with various challenges that explain why the transition to action-oriented knowledge still needs to be fulfilled. Therefore, this paper aims to explore the associated challenges in sustainability assessment in the decision context of the built environment. Several publications are reviewed to provide a systemic understanding of the associated complexities. The challenges in sustainability assessment in the built environment are categorized at different levels, from understanding to measurement and implementation. The challenges are further categorized into definition, context, interpretation, data, measurement methods, uncertainties, indicators and indices, results, coordination, conflicts, and action-oriented knowledge. Moreover, according to the nature of each challenge, they are classified into epistemological, methodological, and procedural challenges. The novelty of this review is that it reviews and reports almost all fragmentedly reported challenges in sustainability assessment of the built environment in the literature within a holistic framework that provides a clear understanding of the state of the art and second discusses them within an integrated framework (the Sustainability Assessment Network) including the position of active-role players to resolve them, including strategists, scientist, and stakeholders.

European Member States are required to promote initiatives and programs to shift their traditional linear economy into circular economy. The paper shows the Italian initiatives towards circular economy in the built environment, across different application level (national and local) and different drivers (top-down and bottom-up). The method of investigation regards an on-field research based on direct dialogue with various stakeholders of construction sector in the national context. The results show the current barriers to circular material flows and the successful initiatives in Italy. Firstly, the top-down strategies are reported, as well as existing standards, national regulations and local policy. Secondly, the bottom-up strategies are shown, stressing the local stakeholders involvement. Based on the discussion, potential improvements are highlighted to align the current Italian initiatives with the broader European Commission circular economy objectives, considering also the best practices developed in other European countries.