The Dollars and Cents of Residential Retrofitting in Australia

The Dollars and Cents of Residential Retrofitting in Australia

Authors:

Daniel Jones

Organisation of Presenter:

University of Wollongong

Abstract:

To date research on the technical challenges and solutions of retrofitting residential buildings have mostly focused on the economics; comparing energy savings and the cost of retrofits and to a lesser degree the interaction between householder behaviour, energy efficiency and retrofit efficacy. There is limited data and research relating to the cost of whole building residential retrofitting in Australia. In Australia and internationally, there is little application of rigorous and transparent methodologies to estimate or measure the cost of residential retrofits. The use of quantity surveying standards or expertise is uncommon and the assumptions used for estimates or measurements of costs are brief or non-existent.

The current research has applied Australian quantity surveying techniques and standards to measure and estimate the cost of detached residential retrofitting in NSW, Australia. Data was collected from eight completed or in-progress retrofit projects to form eight case studies detailing scope, design and costs. Seven of the eight case studies included semi-structured interviews, with the householders who owned and commissioned each project. These interviews investigated the context in which the retrofits took place, documenting the design and specification process and the value and performance of the retrofits following their completion.

The results provided current cost data for retrofits ranging from individual technologies through to whole house upgrades. Additionally, the multi-faceted outcomes possible from retrofits and the implications for economic returns were identified. Improved thermal comfort was the predominant positive outcome reported by householders and in many cases was associated with a small or no economic return. Further to this, economic factors were not the predominant motivation for a number of the retrofits.

These results have implications for governments, revealing the challenges and opportunities inherent in the decision making of early adopters when navigating the design and the implementation phase of home retrofits. Built-environment practitioners and householders interested in the comfort, energy use and environmental impact of houses also benefit from the qualitative data. All of these groups are further equipped to utilise finite budgets to enact energy efficiency, improved thermal comfort and reduced greenhouse gas emission outcomes in the residential built environment.