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The construction industry provides extensive impacts to the environment with population increases further driving these pressures. In an attempt to mitigate these impacts, the industry as a whole has promoted and developed numerous green building rating systems (GBRS). These GBRS assign scores to buildings based on a variety of assessment criteria to determine a structures environmental impact. Previous research has identified shortfalls in certain areas related to these GBRS. In order to gain further insight into these systems an industry survey was conducted to establish an alternate perspective. The outcomes of this survey were consistent with that of previous research, identifying the requirement for an increase in the Embodied Energy (EE) consideration of structures in GBRS. The average estimation of the contribution of EE to a structures life cycle consumption was 28.4%. The survey findings also identified a number of other key areas through which changes in the consideration of sustainable development could be improved. The use of these findings and their comparison to previous research outcomes would assist in the development of supplementary mechanisms to improve the assessment of the environmental performance of structures.

There is currently growing interest in quantifying the direct and indirect carbon emissions embodied in construction materials and their components production. Previous research shows that indirect emission could be higher than direct emission for energy intensity materials such as cement and steel reinforcement. Quantifying direct emissions alone would underestimate the carbon emissions associated with a material and in turn its environmental impact. The assessment of indirect emissions is a challenging task involving upstream processes of material production. This paper investigates the existing literature on the quantification of embodied carbon by both direct and indirect emissions as well as demonstrating the application of a hybrid life cycle assessment method in building construction. The focus of this paper is the Malaysian context however the principles apply universally. A typical 2-storey residential building has been investigated to determine the total carbon emissions when comparing two construction techniques: conventionally reinforced concrete and precast concrete panels. This paper demonstrates the application of hybrid life cycle assessment by expanding the boundaries of process methods and reducing the sensitivities of I–O life cycle assessment to the raw material price fluctuation for product manufacturing.