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.
This study proposes a productization framework to improve the design standardization of rural low-rise prefabricated residences (RLPR) in southern Jiangsu, China. The framework is built on three industrialized structural system prototypes: the prefabricated lightweight steel system (LSSCS), the composite cavity system (CCCS), and the rigid skeleton system (RSCS). At its core is a Python-based algorithmic workflow that automates and optimizes component system standardization. It automatically matches homestead dimensions to suitable layout types and applies combinatorial optimization to structural and enclosure components to minimize component variety. A case study validates the framework. From user-defined constraints, it generates a detailed parametric model and bill of materials, demonstrating a standardized, streamlined, and product-oriented RLPR design process.
Sustainable development is crucial worldwide. Under the Paris Agreement, countries commit to Nationally Determined Contributions (NDCs) assessed every five years. China, a major contributor to global warming, has made significant efforts to reduce carbon emissions and achieve carbon neutrality, a key strategy for sustainable development. However, there is a lack of adequate attention to embodied emission reduction in rural residential construction, despite a surge in building to improve living standards. This paper evaluated the feasibility of applying a multi-ribbed composite wall structure (MRCWS) in rural China through a village service project. A full-scale shaking table test was conducted to study its seismic performance. Carbon emissions were analyzed using process-based life cycle assessment (P-LCA) and the emission-factor approach (EFA), while costs were estimated using life cycle costing (LCC) and the direct cost method (DCM). These analyses focused on sub-projects and specific structural members to validate the superiority of this prefabricated structure over common brick masonry. MRCWS blocks were prefabricated by mixing wheat straw with aerocrete, utilizing agricultural by-products from local farmlands, thus reducing both construction-related carbon emissions and agricultural waste treatment costs. Results show that this novel precast masonry structure exhibits strong seismic resistance, complying with fortification limitations. Its application can reduce embodied carbon emissions and costs by approximately 6% and 10%, respectively, during materialization phases compared to common brick masonry. This new prefabricated building product has significant potential for reducing carbon emissions and costs in rural housing construction while meeting seismic requirements. The recycling of agricultural waste highlights its adaptability, especially in rural areas.