All Humidex® ventilation systems involve a drying out process that will vary, depending on the actual condition of the home, the environment, and other variables. The majority of homeowners will see results relatively quickly, ranging from within a few days to a few short weeks. In extreme conditions, and when there may be heavy moisture saturation in the structure, we recommend that you allow the unit to dry out the basement, for as long as it takes. For the home environment to improve, contributing sources of moisture from water seepage should be remedied first, in order to allow for the basement to dry out. After remedying the water problems and installing the ventilation system, you should start to see improvement. Each home situation is different.