The construction industry is a key contributor to greenhouse gas emissions, with buildings alone accounting for 39% of the global energy-related carbon emissions. Global carbon emissions from building operations increased by 5% in 2021 compared to 2020. However, the United Nations signed the Paris Climate Agreement in 2015 with global leaders, setting a limit to temperature increases below 2.0 °C or 1.5 °C. To achieve this goal, countries have established net-zero targets to reach carbon neutrality by mid-century. However, while some countries are making significant progress, others lag behind. Therefore, this study focuses on evaluating the actions taken by countries toward carbon neutrality, and on developing a policy roadmap for the construction industry to meet the net-zero-carbon commitments. This research adopted a systematic document review, including document analysis. The evaluation of countries’ practices towards achieving net-zero targets reveals both similarities and differences. The policy maps developed can be customised for decarbonising a country’s overall construction industry and building sector. This study provides insights for research, practice, and society, emphasising the importance of achieving net-zero targets through the implementation of policies, roadmaps, plans, and strategies.

Purpose: Any building refurbishment is challenging and school buildings offer no exception. They are increasingly in need of refurbishment due to their age and evolving teaching and learning. The purpose of this paper is to present an overview of literature on sustainable refurbishment so as to identify key lessons from selected successful refurbishment projects. The review findings are expected to contribute to the development of refurbishment plans in an effective and innovative manner that should extend building’s service life, focus on resource efficiency, and comfort their users. It will also contribute to knowledge base of refurbishment and suggest future directions for research. Design/methodology/approach: The paper has undertaken a literature review on the sustainability assessment of buildings and frameworks for sustainable refurbishment. Besides, the work also provides a review of recent successful refurbishment projects to collect and structure systems experiences which can be adopted in developing a sustainable refurbishment strategy for school buildings. Findings: Findings include three groups of lessons in terms of reasons, process and barriers in the selected refurbishment projects that assist stakeholders to prepare a suitable refurbishment plan for their school buildings. The potential of 3D scanners and BIM applications in the refurbishment process will also be reviewed in order to develop a proposed framework of 3D scanner vs BIM for the refurbishment process. Recommendations highlight the role of a national strategy as a driving factor for applying the advantages of information technology to enhance optimal solution selection processes to get better and more sustainable results. Originality/value: The conceptual framework for 3D scanner and BIM applications within sustainable refurbishment for school buildings is currently under researched, and the findings aimed to address such a gap when considering 3D scanners and BIM applications in the refurbishment process.

Several studies have documented benefits of prefabrication system (prefab) compared to the traditional building system (TBS). However, the documented benefits have been anecdotal or fragmented with reports of isolated case study projects. Few studies have looked at the objectively quantified benefits from statistical significance point of view and across building types in New Zealand. This study contributes to filling this knowledge gap by analyzing cost and time-savings, and productivity improvement achievable by the use of prefab in place of the TBS. Records of completion times and final contract values of 66 building projects implemented using prefab in Auckland were collected. The building types included commercial, houses, apartments, educational, and community buildings. The project details included final contract sums, completion dates, gross floor areas, and number of floors. Based on these details, the equivalent completion times and the final cost estimates for similar buildings implemented using the TBS were obtained from the Rawlinsons construction data handbook and feedback from some designers and contractors. Marginal productivity outcome for each building project was computed as the product of the cost and time-savings achieved using the prefab. Results showed that the use of prefab in place of TBS resulted in 34% and 19% average reductions in the completion times and costs, respectively. This also translated to overall 7% average improvement in the productivity outcomes in the building projects. Univariate ANOVA-based hypothesis test results showed that ‘building type’ had no significant effects on the cost and productivity improvement outcomes, but had significant effect on the time savings analyzed in the case study projects. The greatest productivity gain of 11% was achieved in house projects. These evidence-based results could guide optimized use of prefab for specific building application. The hypothesis-testing outcome provides insights on one of several potential influences on prefab improvements, which will be analyzed in subsequent research.