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Old 6/2/18, 11:04 PM
blee2 blee2 is offline
Certified Professional Inspector (CPI) ®
Join Date: May 2015
Location: Portland Oregon
Posts: 90
Default Re: Mystery Black Substance: Not Mold, need help !

That's thermal bridging from outside which makes that area a little colder and it will condense water vapor which collects dust, ash and debris.
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