Ummm...I am not in the crawlspace all the time, but when I do it's usually dry (no musty smell or anything). However, I have noticed the dirt on the vapor barrier looked like droplets, as if water was on the plastic at some point. So I assume it has happened previously. I am pretty sure its not coming from under the vapor barrier. I will say the installation of the vapor barrier is not great (no spikes or tape), but it definitely covers more than 80% of the crawl space. I bought a humidity monitor to see what kind of humidity is in there going forward. What is a normal humidity level?