Radon fan causing increased humidity
Thanks everyone on the feedback concerning humidity and attic insulation. I have discovered the problem. After documenting the temp and RH in both the house and crawl space, I have discovered the Radon Fan is somehow bringing humidity ( outdoor air) into the building envelope. i noted the RH and temp in both the crawl and home with the radon fan running-and I did it in the evening hours so the HVAC or outdoor temps would not alter the findings- but the dedicated dehumidifier in the crawl continued to run. So here we go:
7:30 PM (ac just turned off) indoor: RH 56% / 74 F — Crawl: 52% RH/ 72 F—- Outside: 91% /76 F
11:30 PM ( ac remained off) indoor: RH 47%/74 F—-Crawl : 42% RH/ 74 F—- Outside 90% RH/75 F
12:30 AM ( ac remained off) indoor RH 41% / 74 F—Crawl 40% RH/74 F—-Outside 90 % RH/ 75 F
So I now know its the Radon Fan, making the house humid- but what I’m hoping some incredibly smart building advisor on here would know is why…and how to correct.
Thank you all for your time-this is such a great forum!