What Is the Black Stuff Around My Window Sill?

The windowsill is one place where black mold can grow easily as it is exposed to a lot of water and debris during rainstorms. Black mold on the windowsill is unsightly and can cause health problems as they pathogens from the mold can travel into the home when a lot of wind comes through the window. However, black mold is easily removed and prevented with just a little effort from the homeowner.

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Black mold can grow anywhere, including a windowsill.

Identification

Black mold, also referred to as just mold, comes in a variety of colors; such as black, white, red, orange and yellow. There is also a distinct odor, usually a musty or earthy smell, that comes with the presence of mold. This characteristic often helps homeowners locate mold when it's hidden from view. When it is in the windowsill, the odor may not be noticeable if it's left open all the time.

Cause

Large amounts of standing water and humidity causes black mold to grow in abundance. When there isn't enough ventilation present, black mold will grow where the highest level of water sustenance are located. Enough moisture within the windowsill, though not plainly visible, can be enough for black mold to grow. According to the Toxic Black Mold Information Center, 55 percent humidity or greater for a long stretch of time is enough moisture to trigger a black mold outbreak on windowsills and other surfaces.

Cleaning Up Black Mold

When cleaning up black mold, it is best to put on a pair of rubber gloves first to protect your hands. Fill either a bucket or a spray bottle with warm water and bleach. The bleach will kill the mold quickly and allow you to wipe it away. Spray the mixture directly on the mold and let it sit for five to 10 minutes. Wipe the area using a disposable cloth or a paper towel. Spray more of the mixture as needed. Once you have removed all evidence of the mold, dry the area completely to prevent a reoccurrence.

Considerations

Keep the window open after you cleaned, to help air out the room and allow for good airflow to help dry everything out. To prevent mold from coming back, keep all areas of the home as free of moisture as possible. Clean up any standing water or condensation as quickly as possible. Using a dehumidifier during times of humidity will limit the potential for mold growth.