Where does the water vapor go?
This is a question more of curiosity and needing an education rather than a specific request for advice or guidance on a building issue.
I wonder about this every heating season. So here in southern New Hampshire this past weekend we had a reminder that winter is just the turn of a calendar page away. Fired off my pellet stove for the day Sunday. RH in the house dropped from 60% to about 50% as the temp went from 64F to 72F. During the core of the heating season when that pellet stove runs 24×7 RH will drop over time to 25-30%. This happens in every house during the heating season. Everybody knows that. But did you know that I have no idea where that moisture goes? Heated air holds less water vapor I am told by a10 year old who can’t believe I am even asking the question. OK, I will go with that.
But where does the water vapor not being held by that warmer air go? Is it pushed into the walls and out of the building envelope? Or is the drop in RH just a factor of how RH is measured by my trusty $5 hygrometer?
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