Possible roof leak

Old 05-20-03, 11:29 AM
Visiting Guest
Posts: n/a
Question Possible roof leak

This past winter we had one heavy snow storm. It wasn't until a few weeks later, after it was long gone that I noticed dried moisture areas on the drywall around the ceiling fan vent in the bathroom. I have looked in the attic while it was raining and I see no possible leaks. I have yet to figure out how the ceiling got wet. Could this be the result of the snow melting down into the vent pipe? Any advise on how to prevent it from happening again?
Thank you!
Old 05-20-03, 02:36 PM
Mike Swearingen's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 1999
Location: Northeastern NC On The Albemarle Sound
Posts: 10,701
Upvotes: 0
Received 1 Upvote on 1 Post

The moisture stain was caused by warm, moist air condensation forming in the cold vent pipe in an unheated attic space, and running back down it.
The solution is to insulate the vent pipe in the unheated space. One way is by wrapping insulation batts around the pipe and holding them in place with duct tape. Don't crush the insulation or you'll defeat its purpose. Should help prevent the problem in the future.
Good Luck!
Old 05-22-03, 05:37 AM
Visiting Guest
Posts: n/a

Well the idea that the condensation within the vent pipe in the attic, although it is entirely possible it doesn't explain why it only happened once. If it was condensation caused by the cool air in the attic then wouldn't you agree that the condensation would occur whenever the fan was used during cold weather? This is not the case. Therefore I am back to my original question. After a heavy snow fall why did my ceiling get wet around the fan vent? Now could it be possibly that the vent opening was covered by snow and the fan blowing melted the snow and it dripped into the vent???
Old 05-22-03, 08:28 AM
Join Date: May 2003
Location: Michigan
Posts: 71
Upvotes: 0
Received 0 Upvotes on 0 Posts
Yep. It happened to me. The snow was so heavy that it did cover the vents. When it melted ... well you know the story.

Also had a problem with the sealing of the vent at the roof line .. cracked, hard, weatherbeaten tar. Did you check to make sure this is not a problem?
Old 05-22-03, 09:37 AM
Visiting Guest
Posts: n/a
Thank you! Well I looked but the roof is only 3 years old and I doubt that it would be that worn out by now. I guess I will just have to keep an eye on it. Thanks again

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: