Modelling Vulnerability Of Australian Housing To Severe Wind Events: Past And Present

Vulnerability models for housing during extreme wind events are a critical part of modern catastrophe modelling used to inform insurance pricing, policy-making, emergency management, etc. Historically, the most robust vulnerability model development has taken place in the US. However, since structural systems in the US differ significantly, it is important that Australia-specific models are available and fully described in the literature. Development in Australia has continuously progressed since early works of the 1970s, although much of the research exists in unpublished format. Models from unpublished studies have been used broadly in academia, insurance and by policymakers, in many cases without a clear understanding of underlying assumptions and limitations. The aim of this paper is to provide a review and clarification of these models and introduce the Vulnerability and Adaption to Wind Simulation (VAWS) model, which takes an engineering-based approach. An overview of VAWS program logic and engineering assumptions is presented in addition to a comparison of outputs for one cyclonic region house type with existing models and insurance claims data. For the housing style considered, results suggest that VAWS can provide a better estimate of vulnerability than existing Australian models and those from abroad, not specific to Australian construction.