Hi All
I need advice on attic venting!
This winter i discovererd a few water droplets from 2nd floor ceiling.Upon further inspection in attic i saw the sheathing frosted up from lower soffit area to ridge vent.This is a two story addition thats about 7 years old. The old attic seems ok.The frost was on both sides up to peak.
I checked all penetrations through ceiling wiring plumbing etc. and everthing seems ok. I have gone through this several years ago and found nothing.
I am wondering if the ridge vent is leaking moist air in during snow storms and winds(Michigan) or is it coming up the outside walls?
We have cont. soffit venting and ridge vents in the 3 attic spaces.
Has anybody ever used a vapor barrior paint?
Thanks
Tony
Replies
The most likely source of that sort of moisture on the bottom of roof sheathing in our climate (at least, SE MI/NW OH)is a wet basement or crawlspace.
The last few weeks have been perfect for getting water in crawls and basements: a hard freeze, a deep snow, and a quick thaw. The only place for the snow melt to go is basements and crawl spaces.
Is there also mildew on the sheathing, or just the ice crystals?
I'm seeing ice crystals in most attics these days, and it probably isn't anything to worry about if you aren't also seeing mildew/mold on the bottom of the roof sheathing (indicating a longer term moisture concerns.)
View Image
Sojourners: Christians for Justice and Peace
Bob
Seems to be some mildew on the underside of the sheathing.
The crawlspace is dry(concrete floor) and so is the basement.
Tony
Tony, if there are vents in the bathrooms, where does that go? What you describe appeared here in a clients attic during very cold weather. Broken vent pipe from bath exhaust.
Remodeling Contractor just outside the Glass City.
Quittin' Time
Calvin
Yes the bathroom exhaust is ducted outside to the roof.about 1 foot below ridge vent
Tony
I was at a lecture by a building science guy not long ago... he said several times that moisture barrier paints do not work, in spite of whatever it says on the can.