Controlling Moisture in an Attic
I’m located in Long Island, New York. I’ve recently discovered a large population of insects (psocids) in my attic. These critters apparently thrive in areas of high humidity and where moisture is present, thus leading me to try to find issues with moisture in my attic. The attic seems to be well ventilated, with soffit vents and a ridge vents along the entire length of the roof. I’ve had the attic inspected by two different people who both did not see any issues with mold or excess moisture. Both also said ventilation was adequate.
In terms of temperature humidity, during the day in the summer temperatures will be above 100 degrees with RH in the 20-30% range. Overnight, the temperatures drop into the 70s-80s and humidity rises into the 60-70% range. Humidity levels in the house never rise above 55% typically sitting in the high 40% area, though I’ve been considering using a dehumidifier to lower the levels even further
There are three areas that I can potentially identify that may be causing a moisture issue.
The first is the fact that the people who built the house vented the two bathroom fans directly into the attic. I understand that this needs to be rectified as soon as possible and that I should have those run to the roof and out of the house. I am attempting to contact a roofer to have this done.
The next is the pipes for my air conditioning in the attic. During periods of excess heat and humidity, they definitely sweat. I think this is fairly normal, but perhaps I could add insulation to the pipes to help prevent condensation from forming on the pipes?
Lastly, I do know that my attic is in need of air sealing and better insulation, as there is only fiberglass up there right now and nothing has been air sealed, which I assume can result in a lot of moisture and conditioned air entering the attic. I’ve been looking into having air sealing done and then having cellulose blown in to add to the insulation.
Any advice that someone could provide would be greatly appreciated.
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