The current growing interest in the circular economy (CE) offers extensive opportunities to promote the adoption of more sustainable consumption and production practices across industries, which is a top priority in achieving the United Nations’ Sustainable Development Goals. The construction sector’s shift towards circular models is key to reducing carbon emissions and resource depletion but brings along considerable complexities and challenges, given the industry`s fragmented and conservative nature. Research on CE in construction has been growing exponentially over the past few years, producing a substantial amount of new knowledge in a short time. This study conducted a systematic review to map and synthesise the reported knowledge gaps in the literature. The analysis included forty-one (41) articles published between 2017 and 2022. One hundred fifty-five (155) knowledge gaps were identified and categorised according to seven (7) CE research dimensions—economic, environmental, governmental, methodological, societal, sectoral, and technological—and twenty-six (26) thematic sub-clusters. Findings critically analyse knowledge gaps’ frequency of occurrence over time and across dimensions. A new framework for CE implementation is proposed to support critical discussion and identification of future research trajectories towards a systemic transition to a circular economy in the construction sector. The framework identifies three innovation domains: circular product, circular process, and circular platform.

As cities confront multiple challenges such as climate change, urbanization, and food security, growing attention has been given to sustainable vertical farming and renewable energy solutions. Building facades, typically underutilized in high-density urban environments, present an opportunity for multifunctional buildings composed of both photovoltaic (PV) systems and vertical farming modules. However, on vertical surfaces, these two systems often compete for space. This research focuses on the development of a multifunctional agrivoltaics building envelope (ABE) system, combining building-integrated PV (BIPV) technology with hydroponic vertical farming. This ABE system adopts a modular design approach, where each unit can be prefabricated independently and assembled through an interlocking connection design and bolted fastening to ensure ease of construction and scalability. The design process includes the development of 2D cross-sectional technical design, assembly sequences, and an analysis of key design parameters through 3D modeling. The research adopts a combined Research through Design (RtD) and Research for Design (RfD) approach to bridge prototyping, testing, and performance optimization. This research highlights the potential of integrating renewable energy with agricultural production in building envelope systems. By addressing space optimization and multifunctionality, the research provides a practical framework for future applications in urban sustainability.

Cross-Laminated Timber is one of the most widely used engineered wood products, thanks to its numerous advantages, among which construction speed is the most appreciated, both by clients and by designers. However, construction scheduling compression refers exclusively to CLT structures, while the rest of the construction process still requires a longer phase to complete vertical enclosures. The aim of the research work presented in this paper is to outline advantages brought about when the degree of envelope prefabrication of tall timber buildings is increased. Results are presented in two sections. The first includes the definition of a case study together with an overview of possible technical details for entirely prefabricated façade solutions, ready to be installed without the need to work via scaffolds. The second deals with construction site management analysis for the case study building, where the determination of specific factors having an influence on time and costs is achieved by varying the prefabrication degree of the various façade configurations and repeating the analysis process. The main findings of this research work demonstrate that comprehensive façade prefabrication allows not only consistent compression of construction scheduling to be achieved, but also for immediate protection of wooden elements from weather agents.