I purchased a lot of sheetrock several months ago at a good price. We stored it in a trailer shed which ended up with a branch through the ceiling. Took a couple weeks to notice and now we have mold that has seeped in through the top sheets and through the sides of the ones further down in the pile. The sheets don't look horrible but there are obvious places where mold has grown. Would these still be safe to put in a new home if I sprayed them down with bleach and painted them with killz or am I out the cash. I appreciate any advice.
I think you can save them, but keep in mind Kilz is just a name it doesn't really kill anything. There is a guy on here called Maintaince6 he is very good on mold questions so I would wait till you hear from him.
You've got two problems. First, the drywall got wet enough to grow mold, meaning that the moisture level remained above 60% or .6 water content for greater than 72 hours. That means that it was wet long enough to compromise the strength of the drywall. Second, drywall is very porous and contains enough organic material that the mold has worked it's way well into the sheets. You will never kill what is already embedded. If you use this, and it gets rewetted, the dormant mold will reappear very quickly. The 72 hour window won't apply. If you try to salvage any of it, go 12" past the last sign of mold. I would not plan on using it as is. No matter what you spray on it to kill the mold, it will not penetrate deep enough to eradicate all of the mold components.
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