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Black Mold in Basement

Are you worried that you might have black mold in your basement? Do you notice a musty smell? Is there ugly slime on the walls, cinder blocks or ceiling? Has your basement flooded or is the humidity level high? Are there signs something is damaging your drywall?

Don’t ignore the problem

black mold in basementMolds are not just unsightly; they can cause structural damage and might make you sick.
Black molds may be Stachybotrys, possibly S. chartarum or S. chlorohalonata. Many molds can take up residence in your home. Not all are black; they might be yellow, white or some other color. It’s important to understand and identify molds. Prevent them, if you can, and take steps to get rid of them quickly.


Molds are fungi. They thrive in environments with a high humidity level and put off a musty smell. They are beneficial in nature, helping leaves and other vegetation decompose and enrich the soil.
Molds are everywhere and come in many colors — green, blue, yellow, white, gray and black. Molds reproduce by putting off tiny spores — seed-like organisms that travel through the air. The spores settle on organic materials including food, cardboard, carpeting, fabric, plants, insulation, wood, ceiling tile, drywall, and even cinder blocks and grow — if conditions are right, they grow. If you don’t get rid of them, you can have significant problems!

Types of Mold

There are perhaps as many as 300,000 species, according to the Centers for Disease Control (CDC). It can be difficult to identify types, but you may be able to get an idea based on color. Green, blue or white molds may be Penicillium. Yellow, black or green may be Aspergillus. Alternaria, a common outdoor variety, may be black or gray. Of all them, the most feared are the greenish-black organisms of the genus Stachybotrys. Yes, these infamous “black molds” may be responsible for sick building syndrome and other health problems. Scientists have identified about 50 species of Stachybotrys.

How to Prevent Mold in Basement

Once you have it in your basement, it is very hard to get rid of, and it creates problems that may cost you a lot. Your best course is to prevent the problem. Controlling moisture and the humidity level of your basement is most important.
If you notice a musty smell, check for moisture. Is water seeping in through the cinder blocks? Do you have a leaky pipe? Is your drywall damp? Are there dark splotches on the walls or ceiling? Fungi grow fast in moist, humid conditions, so do regular checks of your basement if it’s a space you don’t often visit.
You may want to invest in a dehumidifier. The cost will be minimal compared to the expense of clean-up and removal. Airflow is necessary, so don’t stack items to the ceiling or very close to walls. Use an exhaust fan or open doors or windows when weather permits. Fungi are attracted to organic material, so don’t grow plants or store firewood in your basement.

How to Get Rid of Black Mold in Basement

how to get rid of black mold in basementYou may have different kinds of molds in your basement. You should get rid of them whether they are yellow, white, green, blue or black.

  • First, remove everything from your basement and make sure it is dry before you try to get rid of your problem. If your insulation, ceiling tiles or drywall are moldy, replacement is your only option. But if it’s only on the surface of painted ceilings, walls, and floors, you should be able to clean it off with a bleach solution. The CDC recommends no more than 1 cup of bleach to 1 gallon of water. Commercial removal products may also be useful.
  • You can scrub cinder blocks and concrete walls and floors with the same solution. You will need to let it soak into cracks and crevices to kill the black mold. Once you get rid of it, and the walls and floor are dry, you can use a sealant and paint. Be sure you have adequate ventilation while working in the basement and wear gloves while cleaning.
  • As you plan for removal, consider steps to prevent further problems. Do whatever you can to maintain control over the humidity level and ensure ventilation in the future.
  • And remember to clean everything you return to your basement. If you have items, such as cardboard boxes, with a musty smell, toss them and get new ones. Compared to starting over, the cost for this black mold clean-up will be small.