© 2019, © 2019 Geographical Society of New South Wales Inc. Home and contents insurance is integral to household and community resilience against disasters. Yet many households are underinsured. While causes for underinsurance have been widely researched, changes to Australian building regulations in the last decade has established a new source of insurance miscalculations. Bushfire Attack Level (BAL) ratings can inflate rebuilding costs by 20% or more, yet BAL ratings remain obfuscated to homeowners and are notoriously confusing to navigate. After the October 2013 bushfires in New South Wales, the Blue Mountains Local Recovery Steering Group found that ‘information on the BAL process, the guidelines, the expected costs, the consulting experts and a property’s bushfire-prone status is literally all over the place’. This paper aims to provide clarity on the subject, tracing the precise socio-technical means through which disaster risk is perceived and assessed. The paper conceptualises insurance and risk ratings as calculative devices that provide both a technical solution to reduce financial losses and a philosophical tool for risk rationalisation. It then builds on interviews conducted with residents in the Blue Mountains affected by the 2013 bushfires, to ascertain how such calculative devices practically affect communities at risk. The paper concludes by outlining potential solutions to a confusing and costly problem in Australia, highlighting critical public awareness issues surround BAL ratings, which have profound insurance and wellbeing implications for people rebuilding and recovering from bushfire.