@aart, Here are pictures of the south facing ventilation opening in question, from inside and out. (The windows on the left side do not open.) It's covered with 1/2" HC, and plastic window screen for bugs. The roof overhang is 6" and sometimes rain/snow blows in. There is another opening just like it on the other (north) end, but the roof over hang is about 12" and nothing had blown in yet.
Oh, I gave the hygrometer a tap. About 15 minutes later, it said the same as the one on the front porch. Percussive maintenance works again!
Oh, I gave the hygrometer a tap. About 15 minutes later, it said the same as the one on the front porch. Percussive maintenance works again!