Condensation between sloped ceiling and roof
I bought my cape style house [suburb of Albany NY), built 1940, three years ago. Over the past year, I see what looks like signs of condensation between roof and wall in the sloped ceiling above the knee wall. The sloped wall paint on the plaster is bubbling. The knee wall space in that room is used for storage. My guess is that conditioned air is getting into that sloped area and getting trapped in the slope. There is a small section in the storage area where it is not sealed by the pine board wall and I can see the insulation -fiberglass with cellulose blown on top of that. I was told the cellulose might have been blown in to remedy this situation. I also read that the cellulose might have caused the problem?? I’ve attached a photo of the sloped ceiling and the storage area. Here is a link to property photos.
Someone suggested it could be a simple fix- fill that small section with great stuff so that the conditioned air doesn’t get in there. Others have suggested it might just be poor quality paint that is chipping off the sloped wall. If that were the case, Wouldn’t it also be chipping off of the ceiling (same paint, same plaster up there)? Of course the Spray foam dealers tell us that the great stuff seal won’t fix it. We love this cute house and plan to live here for the long haul so we want to make the best fix. I will do spray foam if it’s advised but I worry it could even worsen the situation. Is it possible that we just spray foam that sloped ceiling area? Would we need to spray foam the roof deck of the entire attic as well? Gets expensive! The green and frugal fix is what we’re looking for. I’ve read that spray foam can be toxic?? One roofer suggested that installing a solar vent exhaust fan in the attic along with a ridge vent would fix it. We do not currently have a ridge vent nor soffit vents. We have gable vents. We were told that due to the stone and stucco exterior of the house, we cannot install soffit vents. Another roofer told us that there is a way to install soffit vents but maybe they’re not necessary. Our asphalt shingle roof is 18 years old and we’re told it will need replacement in 1-5 years by various roofers. It would be great if that roofer who suggested the fan and vent is correct.
I’m also of course concerned about mold. If my store bought mold test finds bad mold, do I then need professional mold remediation? Everyone has a different opinion so of course we want to do some further research before buying a new roof and/or tearing out plaster walls and changing insulation. Any advice would be much appreciated!
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