 And then when the moisture gets really high, the humidistat will kick on the fan and it will draw some drier air through the crawl space. Now the third thing that you can do is just to be very careful with your outdoor drainage maintenance. So by that I mean make sure you have gutters on the house, that the downspouts are discharging away from the house, and that the soil around the crawl space perimeter slopes away from the house. By trying to keep that water away from those walls, you'll reduce the amount of moisture that's building up in the crawl space. Does that make sense?