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.

The improper disposal of construction and demolition waste (CDW) exacerbates the consumption of raw materials and emissions of greenhouse gasses. In this study, due to the high recycling rate, focusing on the meltable materials of CDW, the recycling phase of CDW is divided into four stages, namely the on-site disposal stage, the transportation stage, the reprocessing stage, and the reproduction stage. Second, based on these four stages, a carbon emission accounting model (CEAM) is established to evaluate the carbon emission benefits of meltable materials during these stages. Third, the CEAM is applied to a typical old residential area to evaluate the carbon emission reduction benefits of the CDW recycling. The results indicate that (1) the full-process carbon emissions of recycled steel, recycled flat glass, and recycled aluminum per unit mass are 677.77 kg/t, 1041.54 kg/t, and 845.39 kg/t, respectively, which are far lower than their corresponding ordinary meltable building materials (OMBMs); (2) the carbon emissions during the reproduction stage represent the primary component of carbon emissions in the MW recycling phase, accounting for 88.52% to 97.45% of the total carbon emissions; and (3) the carbon emissions generated by the recycling of cullet per unit mass are very high, reaching 1768 kg/t, which is 4.3 times that of scrap steel (409.05 kg/t) and 3.6 times that of scrap aluminum (483.76 kg/t). The research findings could provide theoretical methods and experimental data for decision-makers to formulate treatment plans for meltable materials in CDW, thereby empowering urban carbon emission reduction and promoting sustainable development. Construction parties engaged in demolition tasks should enhance on-site sorting and collaborate with recycling companies to ensure its efficient recycling. Recycling companies need to focus on high-carbon-emission stages, such as the reproduction stage, and strengthen technological research to improve carbon reduction benefits.

In the face of contemporary challenges, such as economic instability, environmental degradation, and the urgent global warming crisis, the imperative of sustainability and energy efficiency has reached unparalleled significance. Sustainability encompasses not only the natural environment, but also extends to our immediate surroundings, including the built structures and the communities they serve. Embracing this comprehensive perspective, we embarked on a mission to conceive and construct a model house that harnesses state-of-the-art energy-efficient technologies. Our goal was to seamlessly integrate these features not only to meet our sustainability objectives, but also to mitigate environmental threats.This model embodies a harmonious fusion of indigenous resources, employing locally sourced stone and employing traditional construction techniques. Through this approach, we achieved significant reductions in carbon emissions and established a framework for passive cooling and heating systems. Moreover, the design is intrinsically attuned to its contextual surroundings, preserving the diverse tapestry of regional architectural styles. This study stands as a testament to the potential of innovative design and technology in shaping a sustainable future. The research employs a multi-dimensional approach, encompassing strategies of architectural design with a traditional planning approach, sustainable material selection, energy efficiency, and life cycle assessment across a diverse set of case studies. Building energy analysis is conducted through the application of BIM (Ecotect), providing insights into how BIM can adapt and thrive in various environments. Key findings underscore that thermal performance, minimizing energy loads, and reducing carbon emissions are pivotal aspects in designating a building as both green and energy efficient.