High humidity in between floor space in 2-story home in Zone 3A
Our home has a “crawl” space in between the first floor and second floor, all of our AC duct which is insulated is in this area. It appear to be well insulated, and is the same temperature as the house most of this time, within 1 degree or 2.
The issue is the humidity in this area is 30% higher than inside the house most of the time. The humidity in the house can be as high 58% in this humid season right now, but in the crawl space it is as high 89-90%. It seems like it should not be this different?
There are times in late afternoon that is does go down closer to 10% higher, but not always. we have had recent high rainfall, and it seems to be at it’s worst now, but it can be just as high, even when it was drier outside.
We have checked for roof leaks, and don’t see any signs of water at last where we can tell. Not finding a good consistent reason, so wonder what else to look at and consider, or is it really even an issue, 90% humidity just seems like it should not be that high!
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