My son’s room is incredibly humid. Sometimes 76 percent.
We are in Western Mass. It is south-facing, and the wood clapboards outside get baked by the son. We have mini splits, and had cellulose blown into the wall cavities a couple years ago.
He keeps his A/C quite low, like 68 or 70.
I am vaguely familiar with terms like “vapor drive,” and have limited understanding of building science in general. But after some research, I suspect the sun is driving vapor into the walls, and it is condensing on the back side of his cool plaster walls, then making the room humid.
Does that sound plausible? Is it a result of having cellulose blown in?
And: If this has been happening for a year or two, is there likely a mold problem in his walls? How should I address the humidity, and the possibility of a mold problem?
Thanks for any advice.
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