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Black deposits on framing, 2 layers insulation

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Just did a 40 year old home, damp crawlspace- flat rear yard/no gutters/no vapor barrier on dirt/plumbing leaks. Modest fungus growth on insulation and black spots/deposits on some framing. What exactly are these spots. A mold remediator told me once they were insect/spider droppings, and I accepted it, but didn't see any spider infestation in this house. Would like to know for sure. House also had Owens Corning R-7, 2.25" fiberglass insulation, installed in a double layer under ground floor- much of it installed upside down according to large markings stating "Install this side towards living space". This insulation has black coated kraft paper on both sides of the batt. Why the 2 sided paper? What do you think any negative effect of the two layers and some installed upside down is? No apparent negative effects seen

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It's hard to tell you anything more than what you've said from those two shots. When you take photos of issues, you really need to take establishing shots of the surrounding area that will adequately depict the locations and conditions. Just describing it isn't enough.

The black stuff showing through the paper on the right half of the bottom picture looks like the asphalt emulsion barrier. The black spots showing up on the paper of the overlapping batt to the right looks like it's some kind of fungi.

If it's been like that 40 years and hasn't caused an issue I don't know that it will. Still, I'd recommend they remove the two layers of insulation and replace it with one layer that gives them the R value they want and either use unfaced batts or batts with a vapor barrier on one side only and this time install it in the right location.

ONE TEAM - ONE FIGHT!!!

Mike

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The blacks spots on the floor joist (bottom photo, left) look for all the world like stains from crickets. The stains on the kraft paper are asphalt as Mike said. I see nothing that looks like fungi.

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Dang,

Kevin is right, that is a joist. Guess I'd better start clicking on those thumbnails and viewing them full-size before I put my fingers in motion on the keyboard.

ONE TEAM - ONE FIGHT!!!

Mike

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It there are two layers of vapor barrier, mositure is likely condensing between them createing issues. Yes the paper should be against the subfloor so the insulation is installed wrong and should be reported.

Current NC building practices recommend at least 6 inches of fiberglass batt (R-30). Two layers of 2.25 does not meet current standards.

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Opps! Sorry was mixing R-30 for attics and R-19 for crawlspaces in my head.

You are right. R19, 6" fiberglass batts.

Thanks for keeping me honest.

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