After Flooding, Home Air Tightness Matters in Preventing Mold

Following hurricane and flooding events, air tightness was the most significant factor across regions to predict indoor mold spore concentrations consistently in impacted residential buildings, according to a recent study in Environment International. 

The study analyses showed that the key factors for predicting mold spores are maximum flood depth, presence of a bathroom exhaust fan, central air ventilation, air tightness, and window blind status. 

This study looked at regions in Louisiana, Florida, and the Northeast, and determined air tightness was the most significant factor consistently across regions, while maximum flood depth was less influential in individual regions.  

Maximum flood depth demonstrated a strong and consistent correlation with increased mold spore counts, indicating that areas experiencing greater flood depths are more prone to severe mold issues. When floodwaters recede, these materials often remain damp for extended periods, providing a persistent source of moisture that molds require to thrive, the study found. Factors such as roof age were consistently found to have relatively smaller, yet important impacts on mold spores.