Assessing sustainability performance of built projects: a building process approach

Existing environmental performance assessment approaches focus on the overall performance to reflect sustainability of built projects. However, the impacts caused by construction activities on the environment occur throughout a project's life cycle which may be different at different stages. Similarly, the economic benefits and social impacts from implementing a construction project may be different in different project stages. This paper presents a model of the sustainable development value (SDV), which integrates sustainability assessment into the building process. SDV measures the significance of the concerned project to the attainment of sustainable development values at different stages of a building life cycle, and the SDV at each stage will be amalgamated into the model of sustainable development ability (SDA). SDA is used as a prototype to demonstrate the extent of sustainable performance to aid decision making. This paper presents the methodological framework of SDV and SDA, and the implementation was demonstrated using a case study

A challenge to sustainably improving environmental performance of existing housing stock in Australia

A key global challenge nowadays is to address climate change and reduce greenhouse gas emissions. Climate change is one of the most pressing issues facing Australia today. Improvements to energy and water efficiency of existing building stocks can significantly cut greenhouse gas emissions and reduce utility bills. With increasing recognition that green buildings outperform conventional buildings, much less known about how green building initiatives can be incorporated into upgrading existing housing stocks. In Australia due to population growth and increased in the size of dwellings coupled with the reduction of number of person per household have put an enormous pressue on energy and water consumption. Existing houses represent approximately 98% of residential building stocks and any improvement to these dwellings will have a profound impact on reducing the negative effects of the environment. This paper examines the sustainable upgrading strategies in improving environmental performance of three existing single dwellings. This paper presents an economic analysis of sustainable upgrading using Net Present Value. The results suggest that sustainable upgrading of existing housing stocks is feasible and the scheme will be more attractive if more government financial assistance is provided

Building sustainable score (BSS) - A hybrid process approach for sustainable building assessment in China

Sustainable building in China has gained attention both domestically and abroad. Despite the fast increase in sustainable assessment tools developed locally or adopted from overseas, there are still criticisms about the current situation of weak implementation and lack of comprehensive consideration. The lack of consideration of economic and social as-pects or building performance on whole building life cycle all lead to departure from the true meaning of sustainable development. And lack of participation on the part of stakeholders makes it too theoretical to be carried out. This re-search aims to develop a model to address this problem. This research started with review of current sustainable as-sessment tools applied in China. As the assessment indicators have clear regional disparities, and almost no current tool considers all three pillars of environmental, economic and social in building life cycle. An industry survey was therefore designed for generation of indicators at different building stages, and personal interviews relevant to different occupa-tion in building industry were conducted to complement the questionnaire survey. After that, the model Building Sus-tainable Score (BSS) was developed based on the stakeholders participation. Finally, the model is verified by a case study

Sustainable housing - a case study of heritage building in Hangzhou China

Surrounded by high-rise buildings, some two-storey buildings with black roofs are sited along the Xiaohe (Little River) in the north of Hangzhou, China. The buildings were originally built in the late Qing Dynasty (late 19th century) and restored in 2007 by the Hangzhou municipal government. The architectural materials used in the buildings are mainly concrete for the ground floor and timber to the first floor. Three buildings located at Xiaohe Historical Street were investigated to establish whether traditional buildings performed as well as modern buildings. Hourly temperature and humidity readings from September 2009 to August 2010 were recorded for the selected houses. It was concluded through comparisons that the restored heritage buildings provided similar thermal comfort and conditions to modern buildings

Quantifying and assessing impacts of building processes in a triple bottom line approach

The paper is based on a research project undertaken by the University of Technology, Sydney in examining the integration of economic, social and environmental considerations throughout the building process of a development. The project comprises the first stage, a literature review and model development, followed by the second stage, model implementation through case studies. The paper presents the first stage of the research project in a literature review and model development. The paper reviews the current application of environmental building assessment tools and their impacts on the construction industry. The importance of building process in environmental assessment is also indicated. The paper also seeks to analyze building performance using a triple bottom line approach on a life cycle perspective. The major activities in the building process are identified and presented on how they influence sustainable performance. Finally the paper presents a model that combines economic, social and environmental assessments into a single indicator to aid decision making

Sustainable Maintenance of Office Buildings: The Current Practice in Sydney, Australia

In Australia, approximately 2% of the demand for office buildings is satisfied annually by new construction which means that it will take 50-100 years to replace the current stock and its contribution to the environmental problem. The argument for upgrading existing buildings through sustainable maintenance is strong as it is relatively cheaper and less environmentally costly to upgrade than to rebuild. The upgrading will not only turn old buildings environmentally-friendly but also enhance their market values and competitiveness. This paper examines the role, current practices and limitations of sustainable maintenance of existing office buildings in Sydney, Australia. The paper presents the results of an industry survey conducted in November 2012 on strategies to improve current practices. The survey revealed that the most crucial aspects of sustainable maintenance for existing office buildings are efficient energy and water management; the use of environmentally-friendly materials; improved waste management; education and knowledge of sustainable methods and Government incentives to compensate for any additional costs of sustainable practices. The research found that most existing office buildings in the industry are currently maintained by non-sustainable practices. Sustainability is a relatively new concept but one that professionals are keen to introduce into mainstream practices

Fairness of User Clustering in MIMO Non-Orthogonal Multiple Access Systems

In this letter, a downlink multiple-input-multiple-output non-orthogonal multiple access scenario is considered. We investigate a dynamic user clustering problem from a fairness perspective. In order to solve this optimization problem, three sub-optimal algorithms, namely, top-down A, top-down B, and bottom up, are proposed to realize the different tradeoffs of complexity and throughput of the worst user. In addition, for each given user clustering case, we optimize the power allocation coefficients for the users in each cluster by adopting a bisection search-based algorithm. Numerical results show that the proposed algorithms can lower the complexity with an acceptable degradation on the throughput compared with the exhaustive search method. It is worth noting that the top-down B algorithm can achieve a good tradeoff between the complexity and the throughput among the three proposed algorithms

The influence building codes and fire regulations have on multi-storey timber construction in australia

Timber is an environmentally friendly building material that is both renewable and reusable, though being combustible by nature meant historically it has been viewed in some parts of the world as an inferior structural material to steel and concrete in multi-storey construction. Buildings are responsible for a substantial amount of material and energy consumption. The environmental properties of materials aren't traditionally a design or construction priority and typically cost, performance characteristics and aesthetics have governed the choice of structural materials. This trend is beginning to change as the issues associated with climate change continue to come to the forefront and governments and industry look for ways to assuage its effects. Choosing environmentally sustainable building materials is beginning to become a client and tenant expectation and industry is starting to follow suit. Life Cycle Assessment studies have outlined when timber is used as an alternative structural material to steel and concrete the overall environmental impact of the building can be reduced