Flood economic damage results from complex phenomena involving biophysical processes that determine the damage of the components but also the decisions taken for reconstruction. The method most frequently used to estimate damage is based on the assumption that the property will be restored to its original condition. This method is supported by expert knowledge of damage processes and restoration costs. However, in practice, we wonder about the implementation by individuals of this identical restoration at a time when the build back better is an injunction that is found in many institutional discourses. In France, insurance experts are mandated by insurance companies within the framework of the cat-nat insurance process to ascertain and evaluate the damage suffered by insured persons following a flood. This experience gives them a privileged place to feed the ex ante damage assessment models.</div> <div>However, although, the experts intervene to establish the damage at the very moment when the dwellings are dealing with reconstruction decisions, this profession remains little studied in the literature. In this study, we tried to determine, on the one hand, to what extent the posture of experts influences the assessment of damage and, on the other hand, what role they play in the process of reconstruction and individual adaptation of housing following a flood.</div> <div>Since 2012, we have met with 15 insurance experts, conducted 20 individual interviews and two intermediate workshops on understanding damage mechanisms and estimating repair costs. This work has enabled us to develop damage functions for different sectors (households and economic activities) which were validated during a participatory workshop with the experts.&#160;We will present a critical analysis of this work, focusing on the view of damage held by insurance experts and the underlying assumptions. To complete this analysis, we have carried out additional work specifically on the role of insurance experts in the reconstruction process of households. Through a qualitative field survey in 2021, we met a dozen insurance experts. First, we established the standard expertise process used by the experts. Based on these procedures, we questioned them on how to conduct an expertise. Through narratives, we highlighted the roles that insurance experts actually play with dwellings. In particular, we showed that despite the technical and human skills available to the experts, the issue of reconstruction can only be dealt with informally and remains marginal due to the missions entrusted to the experts by the insurance companies. In conclusion, we will discuss the implication for damage estimation.