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Over the years, the significance of retrofitting has gained much attention with the unveiling of its different applications, such as energy retrofit and deep retrofit, to enhance the climate-resilience of buildings. However, no single study comprehensively assesses the climate-resilience of retrofitting. The purpose of this study is to address this gap via a systematic literature review.

Quality journal studies were selected using the PRISMA method and analysed manually and using scientometrics. Three dimensions of climate-resilience, such as robustness, withstanding and recovery, were used to evaluate the contribution of retrofit measures for achieving climate-resilient houses across four climate zones: tropical, arid, temperate and cold.

Most passive measures can enhance the robustness of residential buildings but cannot verify for withstanding against immediate shocks and timely recovery. However, some passive measures, such as night-time ventilation, show excellent performance over all four climate zones. Active measures such as heating, ventilation and air conditioning and mechanical ventilation with heat recovery, can ensure climate-resilience in all three dimensions in the short-term but contribute to greenhouse gas emissions, further exacerbating the long-term climate. Integrating renewable energy sources can defeat this issue. Thus, all three retrofit strategies should appropriately be adopted together to achieve climate-resilient houses.

Since the research is limited to secondary data, retrofit measures recommended in this research should be further investigated before application.

This review contributes to the knowledge domain of retrofitting by assessing the contribution of different retrofit measures to climate-resilience.

There is an increasing level of recognition of the pressing issues associated with climate change and resource depletion. As a result, it is well recognised that higher education institutions bear responsibilities to promote “sustainable development”. Many universities have adopted green building practices in the construction of their building infrastructure. A variety of Green Building Rating Tools (GBRTs) have been designed to facilitate green building developments. Thus, the aim of this research is to identify mechanisms to improve current GBRTs in terms of waste management (WM) practices by using green star accredited educational buildings in Australia.

A qualitative approach was adopted in this study to achieve the research aim by conducting three case studies of educational buildings in South Australia. Thirty three interviews were carried out in a face-to-face, semi-structured manner and project documentations were reviewed. The participants were asked to provide their expert opinions on the GS initiative and its ability to minimise waste generation, the impact of the GS initiative on solid WM practices and problems associated with the implementation process of the GS initiative. Data was analysed using code-based content analysis using the NVivo software package. Tables and figures were used as the visualization technique to present an expedient understanding in a holistic manner.

Findings showed that the Green Star (GS) initiative drives change in the way current practices are performed in the Australian construction industry. However, this study revealed that WM targets outlined in the GS initiative are not challenging enough. Thus, suggestions are provided in this research to improve the WM aspects of GS initiatives by looking beyond a focus on “sustainability” and “waste minimisation” towards a focus on regenerative environments.

These findings are valuable for practitioners and policymakers seeking to improve WM practices and to address issues associated with climate change and resource depletion.

Sustainable construction is widely considered to be the best practice in construction, helping to create a healthy built environment. Social media is identified as a valuable data source for research on sustainable construction, and Twitter is a popular social media platform in relation to the construction. Green Building construction is identified as one of the methods that promotes sustainable construction. The purpose of this study is to characterise “Green Building” as a topic in Twitter.

Social network analysis methods were applied to a large set of Twitter data related to “green building”. Time sequence analysis and network visualisation were used to characterise Twitter activity and to identify influential users. Text analytics and visualisation methods were applied to the same data set to visualise the text content of Twitter posts relating to green building.

Peaks in Twitter activity were associated with physical “green building” events. The network visualisation of the Twitter data revealed a complex structure and a range of types of interactions. The most “influential” users depended on the ranking method used; however, a number of users had high influence in all measures used. The tweet text visualisation showed evidence of a global and interactive audience on Twitter engaged in conversations about green building. Also, it was found that external links, emoji and popular terms related to a particular topic can be used to increase the engagement of Twitter users on that topic.

Certain Green Building events were observed to be associated with high levels of Twitter activity. The virtual was found to be closely linked to the physical, and for the promotion of green building construction, their respective impact is potentially the most powerful when used in conjunction. The most influential Twitter accounts did not belong to one class of user, including both individuals and organisations. Twitter offers a platform for a range of stakeholders in the area of green building construction to reach a substantial audience and to be influential in the public sphere. The findings of this research provide a valuable reference for industry practitioners and researchers to deepen their understanding of the application of Twitter to green building construction, and the methods of using Twitter to promote important information related to sustainable construction.

Targeting public–private partnership (PPP) projects, the purpose of this paper is to help decision makers fairly allocate financial risk between governments and private investors through a properly designed length of concession period.

On the one hand, the length of the concession period should be long enough to help private investors to achieve their expected profits. On the other hand, the length of a concession period cannot be decided without agreeing on an upper limit, since an overlong concession period takes too much time for governments to recover their investment and leads to an overly lucrative condition for private investors. Following this logic, the concession period decision range is decided, which defines the lower and upper limits for the length of the concession period. The net present values (NPVs) for governments and private investors are estimated via Monte Carlo simulation to better reflect the uncertainties. To further decide on the optimal length of the concession period, the principle of fair risk allocation between governments and private investors is adopted. The concession period, as an important project parameter, should help to minimize the financial risk gap between governments and private investors.

The developed concession period determination process is validated using a numerical example of a PPP transportation project. The analysis outcomes show that the proposed methodology is capable of determining the length of the concession period so as to control private investors’ profit within a reasonable range while achieving a fair allocation of financial risk between governments and private investors. The outcomes also indicate that, before determining the optimal length for the concession period, governments may need to make a choice between better financial risk allocation or stringent profit control for private investors.

The determination process developed here may be inapplicable to social infrastructure PPPs where the income stream is less predictable. In addition, the data analysis targets a highway project with a capital subsidy provided by the government. To strengthen the effectiveness of the proposed determination process, further research should apply the model to PPPs with other kinds of government support.

The concession period for a PPP project is an important parameter and it is a common practice for governments to predetermine the length of the concession period before inviting tenders. The existing models for determining the concession period focus too much on the simulation of NPVs for project parties and neglect the importance of risk allocation in signing and maintaining a long-term contract. There is also a lack of research to evaluate the influence of governments’ preferences on the length of the concession period. To overcome the limitations of the existing models and enrich the methodology for concession period determination, this paper contributes to the body of knowledge by developing a concession period determination process which can help governments to make better decisions. The financial risk is expected to be more evenly shared between governments and private investors with the concession period derived from the proposed process. This determination process is also capable of evaluating the influence of governments’ preferences on the length of the concession period.

Heritage buildings are a crucial part of the UK built sector. They perpetuate a sense of identity, prestige and community. Many heritage buildings however tend to be energy inefficient and the scope for retrofitting such buildings is paramount. Heritage buildings require ratification from planning bodies in order to undertake any alteration on the building. This tends to create a bottleneck in the retrofitting of heritage office buildings. The paper aims to discuss this issue.

This study utilises a case study building in Scotland to evaluate the potential for retrofitting in a UK heritage office building. Building energy simulation software is used to generate the energy data in different retrofit options. A scenario analysis on the heritage status of the building is also undertaken.

The costs, energy consumption and carbon emission levels are evaluated and compared. It was found that the differential in annual energy savings achieved, based on the proportion of capital cost to operational cost, is 14.6 per cent in the heritage building, compared to 24.6 per cent in the non-heritage building.

The study suggests that government and other stakeholders should seek for ways of incentivising retrofit investments in heritage buildings. This will provide an effective way of minimising the contributions of the built environment to global warming and climate change.