In the vast majority of cases the mold growth is caused by condensation.
Attic side sheathing.
The effects of mold exposure depend on your health and the amount of mold you re.
Affix rigid foam insulation to the attic side of the hatch or door.
Add weatherstripping around the perimeter and a sweep to the door of a walk up attic.
Attic spaces are one of the most common places in a home for mold to be found growing.
Mold must be removed from attic sheathing because the spores can cause serious health problems.
Mold on attic sheathing.
Georgia recognized this problem about a decade ago and started requiring all attic kneewalls to have sheathing on the attic side and to be insulated to at least r 18.
Attic hatch or door.
Roof leaks will often lead to a small localized area of attic mold near where the leak is occurring.
Mold growth on attic roof sheathing is a common issue in cool climates such as the pacific northwest.
Below are a few ways to check for possible roof leaks.
Rafters sheathing joists attic side of fascia boards etc.
This occurs when the temperature of the sheathing drops below the dew point creating a thin layer of moisture on the substrate.
Mold on the underside of roof sheathing is also very common.
I ve seen osb oriented strand board.
The best way to provide that sheathing is to use a rigid material.
Use a zippered insulated tent to keep the enclosure draft free attic tent at 7 attic cover insulator 120.