Expert: Ted Barnhill (Principal, Design45 LLC) - 1/2/2008

Question
We bought this house last April.  It was supposed to be rehabbed & looked good...like a rotten cake with pretty icing! We have had the air ducts cleaned, insulation blown into the attic, new blower box under the furnace to  mention just a few of the things we've done.  We also have added a non-vented gas fireplace in the living room.  The house is 1700+ sq. ft.  Every time we think we've got it fixed, something else pops up.  Now our bedroom ceilings are sweating...I mean sweating to the point of water literally dropping from the ceiling.  Before we insulated the attic the entire ceilings were wet.  Now it is just around the outside edges of the room.  Could it be because the insulation was not done correctly?  We've asked the company but they say no.  We don't have any idea of what might be causing this or where to turn to correct it.  Please help!

Answer
Joyce,

Sorry to hear about your moisture problems.  What kind of attic insulation did you add?  Depending on the roof construction, there may be very little room for insulation at the perimeter of the home where the roof meets the walls.  Additionally, if there isn't an air-barrier at that joint, wind from the soffit vents can push blown-in insulation (if that is what you have) back away from the edge.  Your insulation contractor should be able to ensure that this area stays warm, even if it means using a spray-foam at this location.

The other issue you may have is excessive humidity in your home.  Non-vented gas fireplaces are notorious for producing enormous amounts of humidity.  Get a tester and check your humidity; 50 relative humidity is a comfortable level, 60 is considered too high.   If you do have abnormally high humidity, you may want to look into installing an air-to-air heat exchanger on your furnace, or dehumidifiers in key locations.

Good luck, and feel free to follow up with additional questions.  -Ted