Search Results (17)

Accomplishing China’s national targets of carbon peaking and carbon neutrality necessitates proactive solutions, hinging critically on fundamentally transforming rural construction models. Current construction practices in rural areas are characterized by inefficiency, high resource consumption, and reliance on imported materials. These shortcomings not only jeopardize the attainment of climate objectives, but also hinder equitable development between urban and rural regions. Using the Digital Industrial Park in Yongtai County, Fuzhou City, as a case study, this study focuses on prefabricated public buildings in regions with extreme hot–humid climate, and innovatively integrates BIM (Building Information Modeling)-driven carbon modeling with the Gaussian Two-Step Floating Catchment Area (G2SFCA) method for spatial accessibility assessment to investigate the carbon emissions and economic benefits of prefabricated buildings during the embodied stage, and analyzes the spatial accessibility of prefabricated building material suppliers in Fuzhou City and identifies associated bottlenecks, seeking pathways to promote sustainable rural revitalization. Compared with traditional cast-in-situ buildings, embodied carbon emissions of prefabricated during their materialization phase significantly reduced. This dual-perspective approach ensures that the proposed solutions possess both technical rigor and logistical feasibility. Promoting this model across rural areas sharing similar climatic conditions would advance the construction industry’s progress towards the dual carbon goals. Full article

Prefabricated buildings, known for their energy efficiency, environmental benefits, and industrial advantages, play a crucial role in urban renewal. Previous studies on the carbon emissions of prefabricated buildings mainly concentrate on the assessment and auditing of carbon emissions at the materialization and construction phase. Few of them have analyzed the carbon emissions at the operational phase or the influence mechanisms of prefabricated buildings on carbon emissions in urban renewal. Thus, this paper explored the factors and mechanisms that influence carbon emissions in prefabricated buildings in China’s urban renewal. Firstly, the factors that influence the carbon emissions of prefabricated buildings in China’s urban renewal were identified through meta-analysis. Secondly, the theoretical model was developed to illustrate the influence paths of prefabricated buildings on the carbon emissions of urban renewal. Finally, the structural equation model (SEM) was used to test the hypotheses in the theoretical model using data collected from questionnaires. The results show that the carbon emission reduction potential of prefabricated buildings is influenced by four aspects, namely, socioeconomic factors, policy regulations, building operation, and materialization. Policy regulations have the greatest impact on the carbon emissions of prefabricated buildings. They not only directly affect the carbon emissions of urban renewal but also influence carbon emissions indirectly through the social economy aspect. The direct impact of social economy on the carbon emissions of prefabricated buildings is insignificant, while it can indirectly affect the carbon emission reduction in prefabricated buildings by influencing building operations and the materialization stage. The findings could help provide strategies for prefabrication and enhance the reduction potential of urban renewal. Full article

Prefabricated buildings are widely utilized due to their effectiveness in reducing carbon emissions. The construction stage has a significantly higher carbon emission rate than the other stages of their life cycle, but this is difficult to accurately quantify and predict due to the high variability. This study clarifies the system boundary of carbon emissions and the parameters of influence in carbon emissions predictions. The carbon emission quantification model was improved by using the process analysis method and the carbon emission factor method, and a modular calculation formula was proposed. Based on the machine learning algorithm, a carbon emissions prediction model for prefabricated buildings’ construction stage was established and hyperparameter optimization was conducted. A sample database for predicting prefabricated buildings’ carbon emissions during the construction stage was established using a modular quantification method, and the thin plate spline interpolation algorithm was introduced to expand this. The prediction results of carbon emission prediction models using four algorithms, SVR, BPNN, ELM, and RF, were compared and analyzed by RMSE and R². The results show that the model based on BPNN has the highest prediction accuracy when determining the carbon emissions of prefabricated building during the construction stage, and this method can provide a more accurate reference for subsequent quantitative research on carbon emissions from prefabricated buildings. Full article

The building sector significantly contributes to global resource depletion and greenhouse gas emissions, necessitating integrated approaches to evaluate both environmental and economic performance. This study developed a sustainability-oriented assessment framework—applied in a Chinese context—that integrates life cycle assessment (LCA), life cycle costing (LCC), and carbon financial optimization to evaluate the life cycle performance of prefabricated steel buildings. Using publicly available databases (CEADs, Ecoinvent, and the Chinese Life Cycle Database), the framework quantified cradle-to-grave environmental impacts across raw material extraction, prefabrication, transport, on-site assembly, operation, and end-of-life stages. Emissions were monetized using standardized emission factors and official cost coefficients, enabling environmental costs to be expressed in financial terms. A dynamic financial simulation module was incorporated to assess the effects of carbon price fluctuations and quota allocation schemes. Sensitivity analyses were performed to examine the influence of key variables such as retrofit investment costs, emission reduction efficiency, and carbon policy scenarios on financial returns. The results show that material production and operational energy use dominate life cycle carbon emissions, jointly contributing more than 90% of the total impacts. Moderate decarbonization investments—such as HVAC upgrades and improved insulation—can achieve positive net economic returns under baseline carbon pricing. This integrated, data-driven framework serves as a practical decision-support tool for policymakers and industry stakeholders. It is adaptable across different regions and material systems, supporting the global transition toward low-carbon and financially viable construction practices. Full article

The construction industry, which is responsible for nearly 40% of global carbon emissions, is facing increasing pressure to adopt sustainable practices. Traditional construction methods often escalate resource depletion and waste generation, highlighting the need to prioritize sustainability. Life cycle assessment (LCA) is a significant tool for evaluating the environmental impacts of materials across different life cycle stages, yet its application is hindered by data complexities and uncertainties, particularly during the early design phases. Building Information Modeling (BIM) offers a transformative solution by centralizing and automating multidisciplinary data, thus streamlining LCA processes. This study addresses those existing gaps by proposing a structured methodology that integrates BIM with LCA to enhance their applicability during early design. The model leverages BIM’s capabilities to automate data extraction and enable real-time impact assessments by providing precise environmental evaluations of different construction methods. Focusing on modular prefabrication, 3D concrete printing, and conventional construction, this model comparatively evaluates environmental performance across different life cycle phases, highlighting distinct strengths and improvement areas. The Whole Building LCA reveals clear environmental differences, emphasizing modular construction’s substantial opportunities for enhancement to reduce critical impacts such as climate change and fossil depletion. This model supports decision-making, promotes circular economy principles, and aids the construction industry’s transition toward more sustainable practices. Full article

Prefabricated buildings, characterized by factory production, on-site assembly, and efficient and refined management, enhance construction efficiency, reduce building time, and promote material reuse and recycling. The energy consumption (and carbon emissions) during the building operational stage are significantly influenced by the performance of the building envelope component system. To minimize carbon emissions throughout the building’s lifecycle, it is essential to focus on a comprehensive optimization design for carbon reduction in prefabricated envelope systems. This paper draws on grounded theory to construct a system of factors influencing carbon emissions throughout the lifecycle of prefabricated building envelopes. Using a questionnaire survey and leveraging Structural Equation Modeling (SEM), this study identifies key pathways and factors, influencing carbon emissions throughout the lifecycle of building envelope components. It provides insights into carbon emission mechanisms in these components and establishes a comprehensive design pathway for carbon control throughout the lifecycle of building envelope systems. Subsequently, the survey results were analyzed using Structural Equation Modeling (SEM) to identify key factors influencing carbon emissions throughout the lifecycle and their interrelationships. These findings were integrated into the various stages of the whole-process design, yielding actionable recommendations for carbon control in the design process. Additionally, the case study method was employed to illustrate how carbon control design and optimization techniques can be applied at each stage of a specific project, providing a practical demonstration of the research outcomes. The study offers optimized methods for carbon control across the entire process, utilizing optimization strategies to reduce carbon emissions at each stage of the building’s lifecycle. Full article

The traditional construction industry is characterized by high energy consumption and significant carbon emissions, primarily due to its reliance on on-site manual labor and wet operations, which are not only low in mechanization but also result in low material efficiency and substantial construction waste. Prefabricated construction offers a new solution with its efficient production methods, significantly enhancing material utilization and construction efficiency. This paper focuses on the production scheduling optimization of prefabricated components. The production scheduling directly affects the construction speed and cost of prefabricated buildings. Given the complex modeling and numerous constraints faced by the production of prefabricated components, we propose an improved Non-dominated Sorting Genetic Algorithm II (NSGA-II) for multi-objective optimization. The algorithm incorporates adaptive operators and greedy concepts for local search, enhancing solution exploration and diversity. We segment the production of prefabricated components into six stages, analyzing dependencies and constraints, and form a comprehensive scheduling model with objectives of minimizing contract penalties, storage costs, and production time. Extensive experiments demonstrate that the improved NSGA-II provides a more balanced and larger set of solutions compared to baseline algorithms, offering manufacturers a wider range of options. This research contributes to the optimization of production scheduling in the prefabricated construction industry, supporting coordinated, sustainable, automated, and transparent production environments. Full article

In recent years, the topic of climate change has been increasingly noticed by the public, and carbon emission reduction is one of the primary targets for various industries worldwide. The construction industry has a profound influence in this field, so it is significant to consider what kind of efforts can be made in building projects. Many scholars agree to promote prefabrication technology for construction, but its application still faces several challenges. By undertaking desk research, this paper explores the motivation and barriers to adopting modular techniques in construction projects under the lifecycle analysis. The preliminary information of the literature review is collated from dozens of peer-reviewed academic papers. Under the whole lifecycle thought, the PEST analysis tools also present the analytical results. This research finds that the top five barriers are the attitudinal resistance to using modular constructions, lack of sufficient modular expertise and practice, increasing costs and risks on supply chain management, insufficient government support and policy making, and high design and planning requirements. Moreover, the lifecycle analysis can divide the collated barriers into each stage, and adequate government support can assist in promoting the prefabrication in building projects in financial, legal, and technical aspects. The current findings can facilitate the broader use of prefabrication in building projects, improving the environmental sustainability of stakeholders. The process of proposed desk research can also be considered a referenced pattern for other related studies. More first-hand data should be collected and evaluated in further research to improve accuracy and adapt to the newest research field and industrial situations. Full article

In this paper, we explore the integration of building information modeling (BIM) technology to assess carbon emissions, emphasizing the unique contributions to smart and sustainable approaches in prefabricated buildings and focusing on the application of digital construction strategies facilitated by BIM to evaluate carbon emissions in green prefabricated buildings, with a detailed case study on C-House at Southeast University, Nanjing, China. The research methodology involved creating a BIM model of C-House in Rhino and collecting data from the operationalization phase. This research work delves into analyzing the structural components, on-site assembling process, and evaluation of carbon emissions by using a BIM-based assessment, as well as the energy load and consumption of prefabricated components, including sustainable PV panels, to enhance building efficiency and sustainability. The findings uncover the life cycle of C-House, which spans seven stages, compared with the five stages of conventional builds. Currently in its third cycle, C-House exhibits significant reductions of 70.57% in carbon emissions during the second cycle and 43.53% in the first one. This highlights the pattern showing that the prolonged reuse of prefabricated buildings leads to decreasing emissions over time. Such results underscore the potential carbon emission reductions and environmental advantages of reusing green prefabricated buildings. Furthermore, this study provides insights into the entire life cycle of the building, from inception to occupation and post-phase performance evaluation. By employing BIM for modeling, simulation, and analysis, we offer practical insights into the application of smart technologies for sustainable construction practices, significantly contributing to the advancement of green and digital construction technologies. Full article

This study aims to analyze the life-cycle primary energy and climate impacts of structural frames, paying particular attention to the design and prefabrication of different structural materials. The study considers an existing single-story office building with a composite concrete–steel structure and compares it with two functionally equivalent structures, i.e., a conventional reinforced concrete structure and a conventional steel structure. The existing building is located in San Felice sul Panaro, Italy. This study integrates dynamic structural analysis and life-cycle assessment (LCA). The study finds that the use of different materials can reduce the life-cycle primary energy use and CO_2-eq emissions by up to 12%. Furthermore, the benefits derived from the recovery and recycling of materials can reduce the primary energy use and CO_2-eq emissions by up to 47% and 36%, respectively. The prefabrication of structural elements can also reduce the primary energy use and CO_2-eq emissions in the construction stage. A sensitivity analysis considers changes in the electricity supply system and shows that the primary energy and CO_2-eq emissions due to prefabrication decrease when assuming marginal electricity based on renewable energies. This analysis supports the development of sustainable structural design to meet the standards concerning the whole-life-cycle carbon emissions of buildings. Full article

This work employs the carbon emission factor method to offer real-world instances for carbon footprint accounting, allowing for a thorough analysis of the carbon footprint and important influencing elements throughout the materialization stage of prefabricated housing. To identify the 18 important influencing factors that need to be examined from the five stages of building material production, conveyance of building materials, component manufacturing, component transportation, and building, this paper applies the DEMATEL-ISM-MICMAC (Decision-Making Trial and Evaluation Laboratory–Interpretive Structure Modeling–Cross-Influence Matrix Multiplication) model based on data quantification. Following the findings, the case project’s physical phase generated a carbon footprint of approximately 4.68 × 10⁶ kg CO₂. The building materials’ production and processing phase contributed the highest carbon footprint of the entire physical phase, totaling 4,005,935.99 kg CO₂, or 88.24% of the total carbon footprint. To determine the centrality and causality of the influencing factors, four major influencing factors—energy consumption of raw materials (S₄), construction planning and organization (S₁₅), transportation energy type (S₆), and waste disposal (S₂)—were identified using the DEMATEL approach. The influencing factor system hierarchy was divided into six levels using the ISM technique. Level L6, which comprises one influencing factor for organizing and planning, is construction planning and organization (S₁₅). Utilizing the MICMAC technique, it was possible to identify the energy consumption of raw materials (S₄) as the primary cause of the materialization phase of built dwellings’ carbon footprint. The building material production phases have the largest influence on carbon footprints, according to both case accounting and modeling research. The study’s findings can offer some conceptual guidance for the creation of low-carbon emission reduction schemes. Full article

Construction, as an important producer of energy, material, and waste emissions, the high energy consumption problem has not been solved. Prefabricated buildings have become more and more popular and promoted in China in recent years. This study takes prefabricated buildings and traditional cast-in-situ buildings as research objects and divides the buildings into five stages: factory building materials production, component transportation, field installation, use, and demolition. In addition, the paper presents the calculation method of carbon emissions in five stages of construction. By calculating the carbon emissions of the two buildings in five stages, the total carbon emissions of the two buildings and the differences in carbon emissions are obtained. In particular, in this case, the prefabricated buildings and traditional cast-in-situ buildings were constructed at the same time and in the same place. It is concluded that prefabricated buildings can reduce carbon emissions by about 86 kg per square meter compared with traditional cast-in-situ buildings. In all stages of carbon emissions, the field installation stage produces the most carbon emissions. Prefabricated buildings consume more concrete, steel bar, and diesel and fewer wall materials than traditional cast-in-situ buildings. Full article

This study analyzes an office building located in Hangzhou, Zhejiang region, with a high assembly rate of 96.8%. Based on whole-process records and first-hand factory data, using an original method, we empirically investigate the carbon emissions associated to the assembly production and construction phase by comparing the results collected in the field with the calculation results for the simulated non-prefabricated building. The calculation results show that the production and construction stage of the prefabricated office building is characterized by a large reduction in carbon emissions, where the total measured carbon emissions of the subject building were 2265.73 tCO${}_2$e, which is 22 kgCO${}_2$e/m${}^2$ less than that under the non-prefabricated method. In the future development of China’s construction industry, taking Zhejiang Province as an example, the implementation of prefabricated office buildings with a PEC structure system can effectively reduce carbon emissions, which can help China to achieve the carbon peak as soon as possible. Full article

The utilization of prefabricated components is taken as a potential way to reduce carbon emissions from the construction industry, and the prefabrication rate may be a factor that influences the mitigation efficiency. This study develops an assessment method to compare carbon emissions of a building in the construction stage when it is built with multiple different prefabrication rates. Firstly, two carbon sources (building materials and machineries) and three construction sub-phases (production of materials and components, transportation, and on-site construction) are determined to clarify the calculation boundary. Then, a carbon emission measurement model for prefabricated buildings in the construction stage is developed by using a process-based method. A dormitory building in Chongqing, China, is selected to conduct a case study to show the application of the provided model. The result shows that the carbon emission of prefabricated buildings is higher compared to that of traditional cast-in situ buildings. Moreover, the emission of prefabricated buildings decreased slightly with the increase in the prefabrication rate. A detailed discussion is followed to investigate the reason why the carbon emission does not decrease with the utilization of prefabricated units. Based on the discussion, some suggestions are given to improve the carbon emission reduction efficiency of prefabrication techniques. Full article

At present, the issue of carbon emissions from buildings has become a hot topic, and carbon emission reduction is also becoming a political and economic contest for countries. As a result, the government and researchers have gradually begun to attach great importance to the industrialization of low-carbon and energy-saving buildings. The rise of prefabricated buildings has promoted a major transformation of the construction methods in the construction industry, which is conducive to reducing the consumption of resources and energy, and of great significance in promoting the low-carbon emission reduction of industrial buildings. This article mainly studies the calculation model for carbon emissions of the three-stage life cycle of component production, logistics transportation, and on-site installation in the whole construction process of composite beams for prefabricated buildings. The construction of CG-2 composite beams in Fujian province, China, was taken as the example. Based on the life cycle assessment method, carbon emissions from the actual construction process of composite beams were evaluated, and that generated by the composite beam components during the transportation stage by using diesel, gasoline, and electric energy consumption methods were compared in detail. The results show that (1) the carbon emissions generated by composite beams during the production stage were relatively high, accounting for 80.8% of the total carbon emissions, while during the transport stage and installation stage, they only accounted for 7.6% and 11.6%, respectively; and (2) during the transportation stage with three different energy-consuming trucks, the carbon emissions from diesel fuel trucks were higher, reaching 186.05 kg, followed by gasoline trucks, which generated about 115.68 kg; electric trucks produced the lowest, only 12.24 kg. Full article