I recently bought and moved into a bank-owned home that was vacant for about 12 months. A few days after moving in I noticed a fresh wet spot in the living room ceiling that was not there before. I investigated in the attic and found that the dryer vent tube is routed right over the wet area, and indeed the place where the vent tube hits the underside of the roof is directly above the duct junction box beneath which I found moisture.
FYI - I ran this thread in the HVAC forum already thinking it was duct condensation, but I have ruled that out via various experiments. It is not duct condesation.
So in the interest of solving what is now surely a leak, here are a few more photos:
It looks to me like dirty water has run down the outside of the dryer vent tube. You can see the streaks and residue pretty clearly in the photo.
Here's another clue I only just learned of today. My wife tells me the dryer is taking a really long time to dry clothes.
So, is the leak likely caused by a gap in the flashing or tar paper on the roof? Or, since there's an issue with clothes not getting dry, could the vent be blocked or clogged, then filling with water, and THEN running inside the attic somehow???
Thanks for your help.
FYI - I ran this thread in the HVAC forum already thinking it was duct condensation, but I have ruled that out via various experiments. It is not duct condesation.
So in the interest of solving what is now surely a leak, here are a few more photos:


It looks to me like dirty water has run down the outside of the dryer vent tube. You can see the streaks and residue pretty clearly in the photo.
Here's another clue I only just learned of today. My wife tells me the dryer is taking a really long time to dry clothes.
So, is the leak likely caused by a gap in the flashing or tar paper on the roof? Or, since there's an issue with clothes not getting dry, could the vent be blocked or clogged, then filling with water, and THEN running inside the attic somehow???
Thanks for your help.