In this paper, we propose a simplified method and build a model accordingly for estimating the energy-saving potentials of building construction and demolition with the consideration of China's rapid growth of building construction and its short actual lifespan of buildings. To demonstrate the practicability of the proposed method and model, we further develop an illustrative case study to estimate the energy-saving potentials from residential building sector in China. Our results show that a considerable amount of energy-saving potentials can be captured from now until 2020, 2030, or 2050 by smooth implementation of either controlling the growth in demand for the per capita residential building floor area or extending the actual lifespan of the residential buildings in China. Through this study, we fill the gap, in terms of method and model, of supporting the further improvement of China's existing energy conservation policies. (c) 2012 Elsevier Ltd. All rights reserved.