Purpose / Context - The characterisation of the residential building stock existing in Australia in terms of attributes relevant to energy performance is increasingly an important task for planning and policy purposes. There is a lack of information and documentation on the energy performance characteristics of the existing residential stock in Australia, particularly those constructed prior to the introduction of building efficiency regulations; approximately 85% of the 9 million dwellings in Australia (ABS, 2001,2011). This lack of information creates a significant barrier for studies which have attempted to develop representative energy simulation models for existing buildings. Methodology / Approach - Statistical review was undertaken on the Australian residential sector, focussed on buildings constructed between 1970 to 2011, for the purpose of developing representative building simulation models to aid in the quantification of the potential for energy efficiency upgrades. Taguchi and ANOVA methods were used to produce a reduced number of models that incorporated significant parameters for the determination of the energy performance. Differential Sensitivity Analysis (DSA) was then undertaken on a single model to quantify the effect of design parameters on the amount of energy needed for maintaining indoor conditions within a comfortable range. Results – The Taguchi and ANOVA analysis identified floor types, floor area, climate, level of ceiling insulation and wall materials as the most important attributes to be considered in the development of representative simulation models. DSA of design parameters on an example representative model developed in this study showed the parameters with the greatest influence on building energy consumption were airtightness, air conditioning system coefficient of performance, window-to-wall ratio, level of ceiling insulation and glazing SHGC and type. Key Findings / Implications –This study showed the typical Australian residential stock characteristics and potential energy efficacy upgrade strategies. This work has implications of defining the representative dwelling types for current stock, as well as performance assessment of sample dwelling model with investigation of potential energy retrofitting parameters to address the climate change challenge. Originality - The paper provides rather informative overview of Australian residential building stock, structured new contribution in order to defining the referenced building and assessing the effectiveness of specific design parameters towards energy demand loads in dwellings.