Floodplain Price Impacts by Property Type in Boulder County, Colorado: Condominiums Versus Standalone Properties

Studies find various, and often small or negligible, impacts of floodplain designation on home sales prices in the United States, calling into question the U.S.’s National Flood Insurance Program’s (NFIP) effectiveness at internalizing flood risk into the residential property market. However, studies also tend to focus only on standalone homes, although a substantial portion of the U.S. housing market, particularly within designated floodplains, consists of condominiums: single-unit residences that are bundled with an ownership share in common property. This study investigates the price impact of floodplain designation for condominiums and for standalone properties in Boulder County, Colorado, U.S., and finds a strong impact for condominiums but none for standalone properties. Results are consistent across hedonic price estimation and non-parametric matching estimation. Numerous factors may contribute to this difference, including differences in the pre-transaction provision of flood insurance cost information and whether maintaining ongoing flood insurance is compulsory. These results have implications for the NFIP and offer insights for policy interventions for internalizing risks more generally. They also caution against generalizing from the experience of the NFIP without detailed consideration of the contexts and specific conditions in which it is applied.