Notice how the dark line on the insulation in the photo below line up with the top plate.
Mold in attic above bathroom.
What causes black mold in attic.
Mold needs 3 things to grow.
The most common cause of attic mold by far is blocked or insufficient ventilation of the attic space.
Related to 3 above this practice can pump warm moist air into the attic where it can be trapped and begin the cycle of mold growth.
Attics usually have a passive ventilation system in which outside air comes in through the soffit eave vents at the bottom warms up in the attic and escapes through the can or ridge vents at the top because hot air rises.
Insulate the attic space above the bathroom to prevent excessively cold surfaces on the ceiling.
Mold species such as stachybotrys chartarum which looks like slimy growth loves attic basement bathroom and space under the sink black mold can also grow behind the walls or attic ceilings completely undetected until the occupants smell the presence or experience health problems.
Moisture food and warmth.
Dryer vents plumbing vents kitchen or bathroom fans vented into the attic.
This is why you rarely find mold growth in the attic above a garage or a rarely used portion of the home.
Http youtu be pne imqvfoy it shows the things we noticed to d.
Paint the bathroom ceiling with a high sheen gloss paint.
Matte and other low sheen paints absorb much more moisture which in turn leads to mold growth.