Financial Instrument Bundling Under Multiple Market Failures: A Household Risk Layering Approach

Households in disaster-prone environments face multiple market failures-credit constraints, coordination breakdowns and behavioural biases that undermine the effectiveness of standalone financial instruments such as insurance. This paper develops a theoretical model showing that welfare-optimal household disaster risk management requires bundling financial instruments across the ex-ante and ex-post disaster risk management cycle covering prevention, mitigation, coping and recovery, layering tools by hazard probability and severity. We show that bundling dominates single-instrument approaches when it simultaneously relaxes distinct market frictions and is complemented by coordination effectiveness. Numerical simulations illustrate hazard-specific optimal portfolios for frequent floods and rare catastrophic earthquakes. We use two programs from Indonesia to illustrate how strategic bundling can be applied in practice in programme design. The framework provides testable predictions and guidance for designing integrated household financial protection systems in developing countries.