Developing a multi‑hazard retrofit framework for Australian houses: Enhancing structural integrity and reducing greenhouse gas emissions

Many Australian houses constructed before the introduction of current design codes and energy efficiency standards now underperform in both thermal efficiency and structural integrity. Updated regulations further highlight the limitations of older residential stock and the need for practical upgrade strategies. Retrofitting offers a promising pathway to lower building-related carbon emissions while improving resilience. However, Australia lacks an integrated decision-making framework that jointly considers structural and energy upgrades. This study examines the condition of residential buildings, their vulnerability to natural hazards, and available retrofit decision-support approaches. A comprehensive literature review, comparative analysis, and case study-based assessment were conducted to identify pathways for developing a multi-hazard-informed retrofit framework for Australian brick veneer houses. Integrated structural and energy retrofit frameworks have been developed mainly in Europe, particularly for combined seismic and energy upgrades, while comparable approaches remain limited in Australia. The findings also highlight the importance of multi-hazard-based integrated retrofit strategies for reducing life-cycle carbon impacts. As a key contribution, this study proposes a pathway for developing a decision-making framework that addresses retrofit challenges, available optimisation approaches, and the effects of selected natural hazards on the structural and energy performance of Australian brick veneer houses. Simulation- and performance-based approaches, together with optimisation methods, were identified as the most widely adopted strategies, each representing approximately 15% of the reviewed studies. Individual structural retrofit options showed potential carbon footprint reductions of up to 98%, while energy retrofit measures also achieved substantial emission reductions.