Green revolution - a challenge to improve environmental performance of existing housing stocks

Climate change is one of the most pressing issues facing Australia today. This is a challenge and responsibility that is shared by all Australian households. Improvements to energy and water efficiency of houses can significantly cut greenhouse gas emissions and reduce utility bills. In July 2004 the New South Wales (NSW) government introduced the Building Sustainability Index (BASIX) to assess potential performance of a dwelling against a set of pre-determined criteria. Housing construction in NSW is the first in Australia to be subjected to mandatory sustainability requirements. BASIX is an online assessment tool which sets scores required to obtain development approval in new residential projects. BASIX is mandated only to improve environmental performance of new residential buildings and does not attempt to improve environmental performance of existing housing stocks which continue to consume natural resources and pollute the environment. Existing houses represent approximately 98% of residential building stocks in NSW 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 in meeting the minimum BASIX requirements. 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 the payback period is reduced with further government financial assistance