moisture in crawl space

Old 10-24-19, 07:46 AM
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moisture in crawl space

Put new plastic in crawl space. There is drops of water under plastic. moisture reads 12 to 13% in rafters. Is this OK or do I have to do more? Am getting ready to sell house and trying to make it right.
There are small black dots on rafters Brain not working this is under house.
Old 10-24-19, 07:57 AM
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Sounds fine the way it is except, the comment about the black on the joist.
Please post a picture, it may be fungus that's simple to treat.
Old 10-24-19, 09:54 AM
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I hope you used black plastic in the crawl space. It's not required but condensation on the bottom side isn't visible and less likely to attract unwanted attention.

Here is something I stole from another site. The entire article may be found here.

Wood rot only occurs when the moisture content is above the fiber saturation point, about 27% to 28% wood moisture content. In order to keep this in perspective, consider the following: Fresh-cut wood is typically around 200% moisture; that is, twice as much water as wood. Kiln-dried wood has seven to 10% wood moisture content. Air-dried wood has a typical moisture content of 19%, but that varies with the relative humidity (RH). With an RH of 10% and normal temperatures, you can expect wood moisture content to be around 3%. With a relative humidity of 100%, you can expect a wood moisture content of 23 to 26%.

The 28% wood moisture content necessary for rot to occur doesn’t come about from just high humidity. Water has to make contact with the wood before the wood rots. Any time the relative humidity is over 70%, you can get spot condensate because temperatures vary throughout a crawlspace.

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