*
I started building my house in the summer last year. I finished it from the outside before the winter came and now I’m busy working inside. I’ve been insulating the ceiling and the walls for some time. I have nearly finished but yesterday when I went up to the attic I noticed that the roof sheathing on the north side of the house is wet!!! There’s a thin layer of snow on the north side and the south one is clear. From the inside the south side is all right but the other is covered in dew. Is this normal? Can it damage the sheathing? What can I do to stop it? Will it disappear when I finish insulating the ceiling and put the vapor barrier on it? There are eave vents on both sides of the house and a ridge vent up on the roof so everything looked fine to me. I’ll appreciate any suggestions. Thank you a lot.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
The FHB Podcast team weighs in on Building Science career questions.
Featured Video
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
*
Did you have a heater going while you were working ? The warm air from where you were working was probably rising up and condensing on the cold plywood. The sun may have kept the south slope warm enough that nothing condensed there.
You say you have
i "eave vents on both sides of the house and a ridge vent up on the roof".
But did you use proper vents so you didn't block off the air flow at the exterior walls ? If you didn't, all your other ventilation efforts are a waste of time.
*Sorry to corrct Boss Hog, It wasn't warnm air that was condensing. It was water vapour contained in the warm air. This is normal and north slopes see more of it. Finishing insulation and vapour bar will probably take care of it. Don't worry unless it gets worse after closing up.
*Also temp heat like propane or K-1 put out alot of water. Any water not absorbed by the framing has got to go somwhere. Love trimmin those water weight gain, bloated winter houses. When they shrink trim looks great, drywall looks like crap. I also get a kick out of fixin the windows that get caught on the brick as the house shrinks.