The north side of the attic roof has mold. I live in the northeast. Pictures are attached. After some research, I think that the problem is a combination of nails stick out of the plywood and air leaking to the attic. I plan to use a rotary tool to cut all the nails, then use vinegar to clean all the mold. Then I will air seal the attic.
I have a few questions:
Does my assessment sound correct?
My basis is that the only possible source of moisture air other than air leaking is the one venting out of the 2nd floor bathroom. It is vented out to the roof side by a duct pipe. I didn’t see any obvious leaks from the pipe and the pipe is buried under a 6 inch thick insulation foam. The roof has a ridge vent and two windows on both sides. The entire attic is insulated by 6 inch foam.
Should I cut the nails? Will it help? Do I need to add a layer of something to insulate the residual nail top?
My reasoning is that condensed water is visible on the nails. Cutting them will help. One strange thing is that no visible condensed water on nails on the south side of the roof, even at night. I guess that the south side is warmer than the north so less water the mold. Maybe I only need to cut the nail heads of the north side.
Is it easy to air seal the attic? Should I find a professional?
My state has a energy saving program and they provide free assessment of insulation and air leaking. I guess that I will wait for their assessment and then decide what to do.
Thanks in advance for any suggestions.
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