The topic of sustainable affordable housing in developing countries is gaining increasing importance within international debates. The challenge is to find a balance between the concepts of sustainability and affordability in building construction within fragile contexts, overcoming basic self-made shelter solutions towards the creation of sustainable durable housing. In particular, concerning the selection of constructive technological solutions, the goal is to shift from the current decision-making process based only on economic factors to a more holistic approach based on a triple bottom line perspective, integrating economic, environmental and social sustainability. With this aim, this paper proposes a decisional support tool for contexts characterized by poor information to sustain decision-makers in identifying suitable technological solutions. The tool is based on a set of key indicators, articulated into the three pillars of sustainability. The proposed tool, conceived as scalable and replicable, is finally applied to the specific context of Mogadishu (Somalia), since it is representative of the uncertain social, political and economic nature of fragile contexts.

Unlike other industrial sectors that already apply re-manufacturing, the construction sector is slow to experiment with these sustainable practices. Hence, this paper introduces key results of the Re-NetTA project, conducted at Politecnico di Milano and funded by Fondazione Cariplo (2018-0991), which intends to outline the conditions necessary to activate circular processes in the field of tertiary construction. In order to extend the life of construction products, the paper proposes three circular models based on re-manufacturing. Developed with stakeholders and experts in an inter-sectoral and multidisciplinary approach, the proposed models represent a contribution towards sustainable design and organisational practices of construction products.

For updating the construction sector in line with current trends, Life Cycle Thinking (LCT) has to be integrated into the building process from the beginning. In this perspective, the digitalization increasingly assists practitioners in the task, taking advantage in particular of the now widespread Building Information Modeling (BIM). To face construction challenges, the research suggests conceiving BIM as a life cycle database that evolves over time in conjunction with building process development. In this way, to support the players involved in the shift both in thinking and in process, the result of the research is a data collection framework that activates over the process a rigorous life cycle oriented information flow to build up the expected life cycle project-based BIM database. Indeed, since to guarantee the effectiveness of the digitalization process collaboration environments, each stakeholder has to know the requirements of the information content, it points out, based on current practice, the set of life cycle information, the actors in charge and the derived life cycle information flow demanded during the process. The aim is to establish, in one single BIM record, a project-based and well-framed set of data of the facility during the whole life cycle.

In view of the urgent need to construct informed and advanced vision of the built environment in terms of environmental impacts, Life Cycle Assessment (LCA) is even more emerging as the most recognized supporting tool for Architectural, Engineering and Construction (AEC) practices. This is proved by Level(s), a voluntary framework established in Europe that is fully life cycle-based, looking buildings beyond energy performance to the whole life cycle, while fostering the implementation of circular economy strategies. To face buildings complexity, it recommends applying life cycle approach with an increasing level of detail and accuracy, shifting from the assessment of carbon emissions to complete cradle to grave LCA. In this context, many calls for competitions at the reach of environmentally sustainability include Level(s) measures as reference frame to deal with. The paper provides insights of building LCA application performed during the preliminary design phases, since crucial for the decision-making process especially if operating into competition aimed at minimizing environmental impacts. In particular, a sample of building projects developed to address an international architecture competition specifically committed to decarbonization issues in compliance with Level(s) is discussed. Starting from a concrete in situ scenario, the attention is on integrating dry assembled solutions composed of environmental-friendly materials. Results show range of carbon footprint of low-carbon buildings in relation to building shape and volume, outlining building parts that generally contribute to highest release of CO₂ and providing effective technological solutions. The aim is to support AEC practitioners in the design and implementation of buildings embracing a life cycle approach starting from the early design process.