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Community and Q&A

Mold on wall sheathing?

Jmm57 | Posted in General Questions on

We are having a new house built, currently being framed. I stopped by after work today and saw what looks like it could be mold on the brand new wall sheathing. It could also be some sort of ink I suppose, since some lettering on other boards were a very similar color. I was just hoping to get some optnions from the board since you all appear more knowledgeable than me, and possibly save myself from calling out our GC on a non-issue 🙂 Thanks in advance!

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  1. Jmm57 | | #1

    Another pic that shows the ink in a similar color

  2. GBA Editor
    Martin Holladay | | #2

    It's probably mold. In warm, humid weather, it's common to find mold on framing lumber and sheathing. Mold is everywhere -- indoors and out, on manufactured materials and in the woods, as well as in the cheese you enjoy after dinner.

    When your house is dried in, the materials used to build the house will gradually dry out. This process can take a year or two. I wouldn't worry about the mold if I were you.

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