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To fulfil the needs of the future, the Australian building sector seems to contemplate toward sustainable design. A Green Star Environmental Rating System is one of many green-building rating systems that has been employed throughout the world. For this rating system, the “Material” category occupies 14% of credit points, which could be achieved from eight major categories. To help engineers and designers have simple tools to process sustainable projects, this paper develops a computer-aided model to calculate life-cycle greenhouse gas (GHG) emissions for conventional and high-strength concrete to maximize Credit 19B.1: Life-cycle impacts—Concrete in the Green Star Design and As Built in Australia. The model has been built under Microsoft Excel and Visual Basic platforms; thus, it is flexible and appears to be one of the effective ways to provide concrete mixture design using its life-cycle GHG emissions. Options to maximize Credit 19B.1 have also been discussed for normal and high-strength concrete. The model demonstrates the relationship between the utilization of supplementary cementitious material, coarse and fine aggregates used in concrete, a water-to-cement ratio with concrete strength, as well as sustainable points to be achieved. [ABSTRACT FROM AUTHOR]

Solar electricity that is produced from photovoltaic solar systems has the potential to deliver clean sustainable energy. Positive steps are being undertaken to minimise greenhouse gas emissions in Australia and photovoltaic solar systems are contributing towards sustainability. The current amount of installed photovoltaic solar systems cannot address the global warming issues in whole, however renewable energy production is contributing towards minimising carbon emissions. One of the main concerns for the residential householders is the economic issue on the use of photovoltaic solar systems. This paper examines life cycle cost effectiveness in using photovoltaic solar systems with capacities ranging from 1.5 kW to 5 kW in relation to the number of occupants and consumption for residential dwellings over a 25-year period. Eight major cities in Australia, including Sydney, Canberra, Melbourne, Brisbane, Hobart, Adelaide, Darwin and Perth, are investigated. Life cycle cost comparisons among different types of electricity grid connected systems, including a gross-feed-in-tariff (GFIT) scheme, a net-feed-in-tariff (NFIT) scheme and a buy-back scheme, are also explored. It is found that all major cities can receive life cycle cost saving in installing photovoltaic solar systems in their residential dwellings. The life cycle cost saving is between $273 and $53,021 and the percentage of cost saving is between 0.35% and 123.83% in a 15-year period. It appears that the GFIT and NFIT schemes offer better benefits than the buy-back scheme in installing photovoltaic solar systems. It is also found that the higher the capacity of the photovoltaic solar systems, the higher the life cycle cost saving can be received. This paper contributes to prove the cost effectiveness of using photovoltaic solar systems with the example from Australian residential dwellings. [ABSTRACT FROM AUTHOR]

Buildings could be led to adverse impacts on environment, such as generation of construction and demolition waste, and emission of greenhouse gases (GHG). Therefore, promotion on development of green buildings is in need. With the increasing awareness in sustainable development, various rating tools are promoted to evaluate the performance of green buildings. Nowadays, these tools function as a guideline for green building development. There are various green building rating tools developed worldwide, and various countries follow different rules, incentives and regulations. However, despite of promotion of green building rating tools, environmental issues from buildings are still significant in Australia. This research compared green building rating tools in Australia and other countries or regions around the world. This research found that rating tools in Australia lack of (1) mandatory criteria and (2) regulations and incentives. This paper recommended that governmental incentives should be promoted. [ABSTRACT FROM AUTHOR]

Cement is one of the widely used materials in construction. Due to the adverse impacts towards the environment from cement manufacturing, green building rating tools always give a significant consideration towards concrete usage in green buildings. Irrespective of its significance in green buildings, there is a clear lack of research on life-cycle cost (LCC) impact of using supplementary cementitious materials (SCMs) in cement as required by green building rating tools. Therefore, this research analyses the life cycle costs of concrete using SCMs in obtaining concrete credits according to Green Star rating system in Australia. This research used fly ash, slag and silica fume as SCM for concrete. The SCM replacement percentage in concrete ranges from 10% to 60% as higher than 60% substitution is impractical. This research calculated LCC for each replacement percentage and specific building elements in different strength categories. LCC of concrete decreases with higher SCM replacement percentages. Further, there are only slight differences in LCC when comparing the three SCMs. In LCC, the contribution from the initial material cost is approximately 85%–87%, and in an exceptional situation such as in columns, this lowers to 66%. In larger columns, the cost of demolition is greater than that of the initial cost whereas it contributed to 61%–68% of the LCC. [ABSTRACT FROM AUTHOR]

Green buildings are gaining popularity in Australia with the applications of Green Star rating scheme. However, the credit for using timber materials in the rating scheme, while timber being a significantly used material in the fast growing residential construction industry, does not adequately guide designers and builders on the selection of the best timber types for residential applications from the life cycle perspective. This research presents the analysis on the life cycle cost of timber materials in their various applications for residential buildings in Australia and thereby provides guidance on how to best meet the requirement set out in the timber credit in the Green Start rating scheme. Structured interviews were used to collect the data on the cost of timber materials in their lifetime from builders, tradesmen and other residential construction professionals. Three sets of cost information were received under each application, for the individual timber species against three conditions (low, medium and extreme weather) with reference to residential buildings. Based on life cycle cost analysis results, the most suitable timbers for different applications are recommended. [ABSTRACT FROM AUTHOR]