Most studies in the disasters literature rely on convenience sampling and 'after only' designs to assess impacts, which are limitations we address. Focused on Hurricane Harvey and leveraging a pre-sol;post-event sample of Greater Houston households (n=71), this paper establishes baselines for disaster preparedness and home structure flood hazard mitigation; reports on household-level impacts; and examines how preparedness and mitigation relate to post-Harvey health effects, event exposures, and recovery. 70-80% took preparedness measures. Mitigation actions varied with 6% having interior-drainage systems and 83% having elevated indoor heatingsol;cooling components. 60% reported home damage. Half reported allergies and two-thirds indicated some level of post-traumatic stress. Three-quarters worried about family memberssol;friends. Results from generalized linear models revealed that greater pre-event mitigation was associated with fewer physical health problems and adverse experiences, lower post-traumatic stress, and faster recovery. The pre-sol;post-design allowed us to discern broad benefits of home structure flood hazard mitigation for households post-Harvey. This article is protected by copyright. All rights reserved.