Search Results (2,712)

The building sector represents a major frontier in the global response to climate change, accounting for approximately one-third of global energy consumption and a comparable share of energy-related carbon dioxide emissions. This review conducts a PRISMA-ScR–based scoping synthesis of technological, behavioural, and policy pathways to achieve energy efficiency and deep decarbonization in buildings. It systematically examines passive design principles, high-performance envelopes, efficient HVAC and lighting systems, renewable energy integration, building energy modelling, and retrofit strategies. The study also addresses the role of regulatory instruments, energy codes, and certification schemes in accelerating sectoral transformation. The synthesis identifies three cross-cutting drivers of decarbonization: integrated design across building systems, digitalization enabling predictive and adaptive operation, and robust policy frameworks ensuring large-scale implementation. The review concludes that while most technologies required to reach zero-emission buildings are already available, their potential remains underutilized due to fragmented policies, limited retrofit rates, and behavioural barriers. Coordinated implementation across technology, governance, and user engagement is essential to realise a net-zero building sector. Full article

Atmospheric particulate matter (PM) pollution has escalated into a critical threat to urban public health and safety. Among urban functional zones, commercial districts—characterized by high human exposure—are simultaneously hotspots of pollutant accumulation. Consequently, PM mitigation in these areas has become an urgent challenge for sustainable urbanization. This study used Computational Fluid Dynamics (CFD) to simulate the diffusion process and vertical concentration distribution of particulate matter in commercial districts. The results showed that the concentration of PM2.5 decreased with increasing height, with the highest concentration in the respiratory zone (1.5 m) and basic diffusion above 50 m; There are significant differences in the concentration changes of pollutants under different combinations of architectural spaces. By establishing a 20 m block wind corridor, changing the relationship between the building and the street enclosure, and adjusting the form of the building podium and overhead design with building height multiples (6–12 m), strategies can effectively alleviate the accumulation of particulate matter in commercial blocks. These findings provide quantitative evidence for evidence-based retrofitting strategies aimed at reducing PM2.5 exposure in high-density commercial areas. Full article

The sustainable rehabilitation of existing buildings is essential to achieve urban resilience, resource efficiency and seismic risk reduction. This study investigates an integrated retrofit strategy that combines vertical extension with inter-story isolation to simultaneously enhance seismic performance and energy efficiency, creating additional usable space without additional land consumption. The inter-story isolation mechanism reduces seismic demand by decoupling a new and existing structure and introducing beneficial damping effects, whereas vertical extension improves a building’s envelope to reduce energy demands for heating and cooling. A tailored design methodology for integrated intervention is presented, according to which, for the structural part, a two-degrees-of-freedom dynamic model is adopted to design the characteristics of the isolation layer. The methodology is applied to a case-study building located in L’Aquila, Italy, where two alternative vertical extensions, one rigid and one lightweight, are analyzed. Time-history analyses and energy simulations for annual primary energy demand are carried out to assess the structural and thermal performance of the integrated retrofit. The results indicate that the proposed solution can reduce top-floor acceleration by up to 35%, inter-story drift by 30–35%, base shear by over 30% and primary energy demand by 11%, demonstrating its effectiveness in improving both seismic safety and energy performance. The main novelty of this study lies in the systematic integration of inter-story isolation with building envelope enhancement through vertical extension, offering a unified design framework that merges structural and energy retrofitting objectives into a single sustainable intervention. Full article

In this study, the effectiveness of a carbon fiber-reinforced polymer (CFRP) system applied to different regions for the strengthening of historical masonry domes was investigated, and the effects of the CFRP material on the structural performance of different regions were evaluated. One model served as the reference and did not include any reinforcement. In the other three models, reinforcement was applied by wrapping the CFRP around only the skirt region (EPS), only the drum region (EPD), and both the skirt and drum regions (EPSD). The effects of these reinforcement methods on the structural performance were analyzed through experimental tests simulating earthquake effects applied to the dome body wall region. The experimental findings were compared with numerical modeling results obtained using LUSAS V19.0 finite element software, and the overall effectiveness of the reinforcement methods was evaluated holistically. The results show that applying CFRP reinforcement only to the drum (rim) region provides the highest bearing capacity and is the most effective solution in terms of structural performance. Full article

The incorporation of Basalt Fiber-Reinforced Polymer (BFRP) materials marks a significant advancement in the adoption of sustainable and high-performance technologies in structural engineering. This study investigates the flexural behavior of four-meter, two-span continuous reinforced concrete (RC) beams of low and medium compressive strengths (20 MPa and 32 MPa) strengthened or rehabilitated using near-surface mounted (NSM) BFRP ropes. Six RC beam specimens were tested, of which two were strengthened before loading and two were rehabilitated after being preloaded to 70% of their ultimate capacity. The experimental program was complemented by Finite Element Modeling (FEM) and analytical evaluations per ACI 440.2R-08 guidelines. The results demonstrated that NSM-BFRP rope application led to a flexural strength increase ranging from 18% to 44% ductility by approximately 9–11% in strengthened beams and 13–20% in rehabilitated beams, relative to the control specimens. Load-deflection responses showed close alignment between experimental and FEM results, with prediction errors ranging from 0.125% to 7.3%. This study uniquely contributes to the literature by evaluating both strengthening and post-damage rehabilitation of continuous RC beams using NSM-BFRP ropes, a novel and eco-efficient retrofitting technique with proven performance in enhancing structural capacity and serviceability. Full article

Kinetic façades represent a climate-responsive design solution that improves building adaptability by responding to seasonal needs such as daylighting and shading. They offer an attractive retrofit strategy that improves both the esthetics and environmental performance of buildings. This study investigated the integration of an origami-inspired kinetic façade into a student dormitory building located in Dhahran, Saudi Arabia. Using numerical simulations, 35 façade configurations were analyzed under varying conditions of façade orientations, closure ratios (from 5% to 95%), and cavity depths (from 20 cm to 100 cm). The findings highlight the critical impact of kinetic façade design characteristics on daylight availability and solar exposure and the required trade-off between these two variables. In this context, this study observed that at higher façade closure ratios, increasing cavity depth could effectively mitigate daylight reduction by promoting reflected daylight penetration inside the cavity. As for heat gains and cooling load reduction, mid-range façade closure, 50 cm in this study, achieved balanced performance across the three examined orientations. However, the southern façade showed slightly higher efficiency compared to the eastern and western façades, which achieved lower cooling reductions and showed a similar UDI compromise. Thus, a dynamic façade operation is recommended, where higher closure ratios could be applied during peak solar hours on the east in the morning and the west in the afternoon to maximize cooling savings, while moderate closure ratios can be maintained on the south to preserve daylight. Future work should incorporate real-time climatic data and smart control technologies to further optimize kinetic façade performance. Full article

This study presents the Level(s)+37 Framework, a decision-support tool consisting of 37 indicators designed to evaluate and enhance passive design performance, social equity, and climate resilience in primary and secondary schools. Aligned with the six macro-objectives of the European Level(s) scheme, the indicators are organised into seven thematic clusters—thermal comfort, indoor air quality, solar control and daylighting, environmental ergonomics, ecological sustainability and circular economy, climate justice and social equity, and educational value with stakeholder participation—covering all life-cycle stages from design to retrofit. The framework was developed through a six-phase mixed-methods protocol, including a systematic review of 210 scientific and regulatory sources, 24 semi-structured interviews with school stakeholders, and a Delphi–AHP involving 170 experts. The resulting hierarchy of indicators (CI < 0.10; Kendall’s W = 0.78) ensures methodological robustness and contextual relevance for the Spanish school building stock. By integrating environmental, technical, and pedagogical dimensions, the Level(s)+37 Framework serves as both an evaluation tool and a catalyst for sustainable transformation, promoting participatory governance and climate-responsive learning environments. Full article

Improving the energy efficiency of traditional production methods while preserving their cultural and economic value is a challenge aligned with the Sustainable Development Goals of the 2030 agenda. Refrigeration during cheese maturation is particularly energy-intensive, contributing significantly to greenhouse gas emissions and operating costs. An approach to make traditional cheese production more sustainable, through the development of a prototype ripening chamber with a natural refrigerant-based refrigeration system powered by renewable energy was studied. A dedicated system based on an Internet of Things architecture was developed using low-cost sensors, microcontroller units, and single-board computers to enable real-time measurement and monitoring of environmental variables and energy consumption throughout the ripening process. A comparative analysis was conducted using ewe’s milk cheese, produced and ripened with Protected Designation of Origin conditions, in both the prototype and the conventional chambers over four weeks, quantifying energy consumption and evaluating product quality. Results demonstrate the technical feasibility of energy efficient and sustainable refrigeration systems, as well as the possibility of retrofitting installed cheese ripening chambers with affordable IoT monitoring systems, while maintaining traditional cheese quality standards. Full article

Blast damage to structural members poses serious risks to both buildings and people, making it important to understand how these elements behave under extreme loads. Columns in reinforced concrete (RC) structures are especially critical, as their sudden failure can trigger progressive collapse, unlike beams or slabs that have more redundancy. This state-of-the-art review brings together the current knowledge of the blast response of RC columns, focusing on their failure patterns, dynamic behavior, and key loading mechanisms. The studies covered include experiments, high-fidelity numerical simulations, emerging machine learning approaches, and analytical models for columns of different shapes (square, rectangular, circular) and strengthening methods, such as fiber reinforcement, steel-concrete composite confinement, and advanced retrofitting. Composite columns are also reviewed to compare their hybrid confinement and energy-absorption advantages over conventional RC members. Over forty specific studies on RC columns were analyzed, comparing the results based on geometry, reinforcement detailing, materials, and blast conditions. Both near-field and contact detonations were examined, along with factors like axial load, standoff distance, and confinement. This review shows that RC columns respond very differently to blasts depending on their shape and reinforcement. Square, rectangular, and circular sections fail in distinct ways. Use of ultra-high-performance concrete, steel fibers, steel-concrete composite, and fiber-reinforced polymer retrofits greatly improves peak and residual load capacity. Ultra-high-performance concrete can retain a significantly higher fraction of axial load (often >70%) after strong blasts, compared to ~40% in conventional high-strength RC under similar conditions. Larger sections, closer stirrups, higher transverse reinforcement, and good confinement reduce spalling, shear failure, and mid-height displacement. Fiber-reinforced polymer and steel-fiber wraps typically improve residual strength by 10–15%, while composite columns with steel cores remain stiff and absorb more energy post-blast. Advanced finite element simulations and machine learning models now predict displacements, damage, and residual capacity more accurately than older methods. However, gaps remain. Current design codes of practice simplify blast loads and often do not account for localized damage, near-field effects, complex boundary conditions, or pre-existing structural weaknesses. Further research is needed on cost-effective, durable, and practical retrofitting strategies using advanced materials. This review stands apart from conventional literature reviews by combining experimental results, numerical analysis, and data-driven insights. It offers a clear, quantitative, and comparative view of RC column behavior under blast loading, identifies key knowledge gaps, and points the way for future design improvements. Full article

A rapid review was undertaken to consider the evidence for human exposure to harmful microorganisms from indoor air and surfaces. Published information about these contaminants, as well as measures to control them, including building design and energy conservation, were included in this review. Information on domestic dwellings, office environments, and other non-industrial settings was assessed to determine the reported prevalence, persistence, and transmission of microorganisms in these settings. Environmental factors that influence indoor microbiological colonization were also included. The evidence strongly indicates that ventilation is the primary factor for controlling indoor dampness, helping to mitigate indoor mold colonization and the accumulation of other indoor contaminants, including infectious microorganisms. Although modern building airtightness, including retrofits of older builds, contributes to thermal comfort and building energy efficiency, this may also limit a building’s ventilation capacity. This in turn can potentially allow biological pollutants to accumulate, increasing the likelihood of harmful exposures and ill-health effects for building occupants. Effective building design and maintenance, which promote appropriate levels of air exchange for indoor spaces, are therefore important for the control of indoor moisture and microbiological contamination. Full article

With the goal of achieving carbon neutrality, promoting the clean and low-carbon transformation of energy assets, as exemplified by existing thermal power units, has emerged as a pivotal challenge in addressing climate change and achieving sustainable development. Arrangements and technologies such as the electricity–carbon–certificate multi-market, microgrids with direct green power connections, and carbon capture and storage (CCS) retrofitting provide favorable conditions for facing the aforementioned challenge. Based on an analysis of how liquid-storage CCS retrofitting affects the flexibility of thermal power units, this manuscript proposes a bi-level optimization model and solution method for capacity allocation for grid-connected microgrids, while considering CCS retrofits under multi-markets. This approach overcomes two key deficiencies in the existing research: first, neglecting the relationship between electricity–carbon coupling characteristics and unit flexibility and its potential impacts, and second, the significant deviation of scenarios constructed from real policy and market environments, which limits its ability to provide timely and relevant references. A case study in southern China demonstrates that first, multi-market implementation significantly boosts microgrids’ investment in and absolute consumption of renewable energy. However, its effect on reducing carbon emissions is limited, and renewable power curtailment may surge, potentially deviating from the original intent of carbon neutrality policies. In this case study, renewable energy installed capacity and consumption rose by 17.09% and 22.64%, respectively, while net carbon emissions decreased by only 3.32%, and curtailed power nearly doubled. Second, introducing liquid-storage CCS, which decouples the CO₂ absorption and desorption processes, into the capacity allocation significantly enhances microgrid flexibility, markedly reduces the risk of overcapacity in renewable energy units, and enhances investment efficiency. In this case study, following CCS retrofits, renewable energy unit installed capacity decreased by 24%, while consumption dropped by only 7.28%, utilization hours increased by 22%, and the curtailment declined by 78.05%. Third, although CCS retrofitting can significantly reduce microgrid carbon emissions, factors such as current carbon prices, technological efficiency, and economic characteristics hinder large-scale adoption. In this case study, under multi-markets, CCS retrofitting reduced net carbon emissions by 86.16%, but the annualized total cost rose by 3.68%. Finally, based on the aforementioned findings, this manuscript discusses implications for microgrid development decision making, CCS industrialization, and market mechanisms from the perspectives of research directions, policy formulation, and practical work. Full article

The industrial motor systems account for 45% of global electricity consumption. A life cycle model is established to quantify the potential environmental benefits of typical adjustable permanent magnet drives (APMDs, 1250 kW) versus variable frequency drives (VFDs) in China. The model covers mining of metals, manufacturing, operation, and recycling phases of APMDs, incorporating empirical data from China’s 3232 coal-fired units. Four scenarios are set up: business-as-usual, moderate, aggressive, and full-retrofit. Key findings demonstrate that APMDs reduce operational energy consumption by 94.5% compared to VFDs through significantly declining frequency conversion losses and cooling requirements. The life cycle carbon emissions of APMDs (29.7 tonnes CO₂_eq) represent merely 5% of VFDs emissions (570 tonnes CO₂_eq), achieving a 95% reduction. Within APMDs’ footprint, recycling contributes a 45% emission offset (−13.3 tonnes CO₂-eq), while operational efficiency drives the majority of the reduction. Sensitivity analysis identifies electricity emission factors, NdFeB production emissions, and metal recycling rates as primary sensitivity drivers (sensitivity index ST = 0.80). Scenario simulations confirm that the aggressive retrofit strategy (covering high- and moderate-potential units) could reduce annual GHG emissions of 3.12 million tonnes CO₂_eq., with corresponding 89% decreases in particulate matter (PM). This research demonstrates that APMDs are an effective pathway for the low-carbon transition in coal power systems. Their large-scale implementation can potentially necessitate breakthroughs in tiered retrofit policies, thereby providing crucial technological support for industrial carbon neutrality. Full article

In recent years, European and national policies on energy efficiency and sustainable construction have promoted a profound rethinking of building practices and strategies for upgrading the existing building stock. With the conversion of Law Decree No. 34 of 19 May 2020 (Decreto Rilancio) into Law No. 77 of 17 July 2020, and of Law Decree No. 76 of 16 July 2020 (Decreto Semplificazioni) into Law No. 120 of 11 September 2020, the tax deduction rate was increased to 110% for expenses related to specific interventions such as seismic risk reduction, energy retrofit, installation of photovoltaic systems, and charging infrastructures for electric vehicles in buildings—commonly known as the Superbonus 110%. Furthermore, the category of “building renovation,” as defined in Presidential Decree No. 380 of 6 June 2001 (art. 3, paragraph 1, letter d), was expanded with specific reference to demolition and reconstruction of existing buildings, allowing—under certain conditions—interventions that do not comply with the original footprint, façades, site layout, volumetric features, or typological characteristics. These measures were designed not only to positively affect household investment levels, thereby significantly contributing to national income growth, but also to support the broader objective of decarbonising the building sector while improving seismic safety. Within this regulatory and policy framework, instruments such as the Superbonus 110% have acted as a driving force for the diffusion of renovation projects aimed at enhancing energy performance and reducing greenhouse gas emissions, in line with the objectives of the European Green Deal and the Energy Performance of Buildings Directive (EPBD). This paper is situated within such a context and examines a real-world case of bio-based renovation admitted to fiscal incentives under the Superbonus 110%. The focus is placed on the procedural framework as well as on the technical, economic, and evaluative aspects, adopting a multidimensional perspective that combines regulatory, operational, and financial considerations. The case study concerns the demolition and reconstruction of a single-family residential chalet, designed according to near-Zero-Energy Building (nZEB) standards, located in the municipality of San Roberto, in the province of Reggio Calabria. The intervention is set within an environmentally and culturally sensitive area, being situated in the Aspromonte National Park and subject to landscape protection restrictions under Article 142 of Legislative Decree No. 42/2004. The aim of the study is to highlight, through the analysis of this case, both the opportunities and the challenges of applying the Superbonus 110% in protected contexts. By doing so, it seeks to contribute to the scientific debate on the interplay between incentive-based regulations, energy sustainability, and landscape–environmental protection requirements, while providing insights for academics, practitioners, and policymakers engaged in the ecological transition of the construction sector. Full article

Fiber-reinforced polymer (FRP) composites have become a popular solution for upgrading reinforced concrete (RC) structures due to their corrosion resistance, high strength-to-weight ratio, and speed of implementation. However, their organic resin binder has issues, including temperature sensitivity, poor performance in moist conditions, a high cost, and potential health risks. Additionally, reversing FRP repair can be difficult and may damage the original structure, posing a significant reversibility issue. A promising alternative to FRP is the fiber-reinforced cementitious matrix (FRCM), which replaces the organic resin with an inorganic cementitious mortar. This new class of composite uses a breathable textile instead of the tightly packed fibers in FRP. The present article provides a comprehensive assessment of the two composites (FRP and FRCM) used for the retrofitting of RC compression members, with the purpose of identifying existing knowledge gaps and outlining future research objectives. The materials used in different strengthening approaches using both FRP and FRCM have been identified, and their stress–strain characteristics under tensile load have been outlined. The study also explores techniques of implementation using the two materials. This study presents available studies comparing the utilization of FRCM composites with FRP for the axial retrofitting of RC compression members in both ambient and high-temperature conditions. Full article

Joist floor systems are usually employed in buildings of the Middle Eastern regions. These systems usually have reinforced concrete (RC) wide beams, which in many cases have planted columns in non-seismic regions due to architectural requirements. Changes in building use can increase the loads on these columns, which may increase the shear demand of beams to a level that may exceed their capacity. Consequently, upgrading of such wide beams against shear is crucial. This study investigates two strengthening techniques to enhance the shear performance of RC wide beams with planted columns through experimental testing and analytical evaluation. Four half-scale specimens were tested: two unstrengthened beams (one code-compliant and one shear-deficient) and two strengthened beams, using either externally bonded steel plates or a combination of CFRP U-wraps with planted steel U-stirrups. The performance of the retrofitting schemes was assessed based on failure modes and load-deflection responses. The second strengthening scheme improved the shear resistance of wide beams by 82% compared to the control specimen. Additionally, the shear capacity of the tested beams was analytically predicted, and the results were compared with the test findings, providing insights into the effectiveness of both strengthening methods. Full article