Hey, I just wanted to put this out to you guys and see if you have any suggestions. I have never run across this situation, as everything I have ever built was either totally replaced with new stuff, or built new. So, here’s my problem. I had to marriage an addition onto a double wide. In order for the roofs to line up, I had to use 2×4’s for the rafters because the ceilings were to line up as well. Anyway, my basic problem is, when I built the roof, I was concerned about moisture building up on the underside of the roof sheeting. So I put rafter mates in between the rafters and it left me very little room for insulation. The ceiling was to be tongue and grove pine, so I used that aluminum foil (bubble wrap) stuff that was supposed to give an equal insulation value as R-19. So, I have the shingles, the felt paper, the 3/4 sheeting, rafter mates, insulation and tongue and grove pine.
I think I am getting moisture from inside, getting sucked into the rafter mates and causing condensation. I believe the culprit is mostly because there hasn’t been any finish trim installed yet. So pretty much all the way around the ceiling there is a 1/2” to 3/4” gap. So I think warm air is getting sucked up into the sheeting and condensing and running down a rafter, because the water is seeping out of only one spot an one rafter. It is right over where the door that leads into the double wide from the addition is. So this leads me to believe that as the door from the house is opened, warmer air is exiting the door, rising and condensing in the ceiling and running down the rafter to the wall.
This was a concern of mine from the get go, so when I installed the “bubble wrap”, which I had never used before, I taped it onto all the walls with aluminum tape. Here’s my thinking, before installing the 2” wide trim, I wanted to seal this gap between the walls and the pine on the ceiling with something, then cover it with trim. I was initially thinking tape, but i wanted to see if you guys had any other ideas….Any thing would be appreciated. Thanks in advance, Todd
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