Reducing Attic Condensation

 

CHRIS: I have a three-year-old house and I have an air handler that’s up in my attic and the air handler has a 16-inch flex tube that goes out to my living room.

 

TOM: OK.

 

CHRIS: And it is collecting moisture during the winter months.

 

TOM: Do you have condensation that’s inside of it, Chris?

 

CHRIS: Lots of it. And it’s leaking down the living room wall.

 

TOM: Wow. Was the flex duct securely connected to the register?

 

CHRIS: Yes.

 

TOM: OK. Because I think there’s a leak in there. Two things you can do: first of all, I would check all the connections on the ducts; and, secondly, I would take some steps to reduce the amount of humidity up in that attic space. A three-year-old house, I’m going to guess, that probably doesn’t have enough attic ventilation because builders tend to under-ventilate these days, what we’d like to see is a continuous ridge and soffit vent and we want to make sure that the type of ridge and soffit vent that are selected really have a lot of opening, too. Some of the vent systems that are out there now don’t seem to have very much airflow, but if you flush out that attic with as much passive ventilation as you possibly can, that’s going to reduce the condensation considerably.

 

CHRIS: OK.

 

TOM: And the other thing that you can do is you can add additional insulation on top of that duct so that the warm, moist air that’s coming up from the house doesn’t strike a super-cold duct and condense. So three things: check the connections, improve the attic ventilation and add some more insulation around the duct systems.

 

CHRIS: OK, thank you very much.

 

TOM: You’re welcome, Chris. Thanks so much for calling us at 888-MONEY-PIT.