A resilience-based framework for assessing socio-economic indirect losses from natural hazards

The built environment is increasingly exposed to more frequent and intense climate-related extreme events. Although numerous frameworks exist to assess the impacts of extreme events - usually measured in terms of deaths, dollars and downtime - several authors have shown that indirect losses, often driven by the recovery phase rather than the response one, can represent most of community losses. Delays in initiating repairs significantly increase indirect losses but are often overlooked in frameworks focused only on immediate response. While recent resili- ence-based approaches aim to include both response and recovery, their indices often lack clear links to measurable physical outcomes. The definition of a clear, relatable, scalar index could better inform stakeholders and decision-makers about potential risks and guide them in planning mitigation strategies. This paper proposes a novel framework for quantifying socio-economic (direct and indirect) losses by considering both the response and recovery phases of extreme events. Building on resilience principles and functionality-time curves, this framework offers a comprehensive yet practical method for quantifying indirect losses. The approach is validated through a multi- story building subject to earthquake and flood hazards, by employing a component-based prob- abilistic loss modelling approach. The framework was able to provide an estimation of indirect losses due to business interruption showing how indirect losses can match or even exceed the direct economic losses due to damage repairs.