09/02/2026
Not all jobs come out brand new . Setting customer expectations and explaining the root causes is critical before any cleaning takes place . The stains around roofing nails is more than mold , they are Iron Tannate Stains. This forms when dissolved iron ions from the nail chemically bond with the natural tannic acid (tannins) inside the wood sheathing. This is the exact same chemical combination historically used to make permanent black ink (iron gall ink). It locks itself into the cellular structure of the wood, which is mold cleaners cannot fade this stain.
