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Identify & Prevent: Types of Mold in Houses

Dangerous mold could be growing in your crawl space or basement -here’s how to protect your family from toxic molds.

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Is your family at risk from toxic mold growing inside your home? Mold can grow unseen in a home’s interior, including inside damp basements and crawl spaces. Mold growth can damage the structural integrity of your home and cause health problems for the people living there. 

Do you live in one of the country’s top locations for mold growth? Last year, residents in Washington, D.C., as well as Kansas, Tennessee, Connecticut, New Hampshire, West Virginia, New York, Kentucky, Illinois, and Missouri were most apt to search online for “mold removal” according to Google. Three million Americans are treated for allergies related to mold exposure every year. From causing allergies to impacting asthma, mold can harm the health of our families if left unchecked inside the home.

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Types of Dangerous Mold in the Home and How to Protect Against it
Created By: Groundworks

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According to the US Environmental Protection Agency, the most common types of mold found growing inside homes throughout the U.S. are Cladosporium, Penicillium, Alternaria, and Stachybotrys chartarum. Mold growth is common and happens both indoors and outdoors throughout the country. Mold actually plays a valuable role in our ecosystem, but mold growing indoors can cause health issues and structural damage to a home. Each of the common mold types can damage the air quality inside a home. In addition, Stachybotrys chartarum is a dangerous and toxic mold type that should be removed immediately if found indoors.

How To Find and Identify Common Mold Types

  • Cladosporium is most often found in moisture-heavy areas of the home, including basements and bathrooms. It usually grows on acrylic painted walls, wood, carpets, wallpaper, or other damp organic materials. Cladosporium can come in many different kinds and colors, including green, brown, gray, and black.
  • Penicillium is found most often on spoiled food, but can also grow on moist walls, wallpaper, floors, and carpet. It is usually blue, yellow, green, or white-colored.     
  • Alternaria is a common cause of allergies. It is dark gray, grows in spots and can most often be found growing on tiles, bricks, plaster, wallpaper, paper, canvas, and iron materials.      

How To Identify Toxic Black Mold

The most dangerous type of mold found indoors is Stachybotrys chartarum, often called “black mold.” Black mold is toxic to humans and pets. Luckily, it is less common than the other three mold types in the U.S. It is difficult to identify however, because other mold types can grow black in color as well. Because it is hard to tell the difference between black mold and other types, the Center for Disease Control recommends removing all mold immediately.

Stachybotrys chartarum is greenish-black in color and can emit a musty or rotten smell. It is most often found growing near water damage inside a home, including on damp building materials. A good example of where you might find this type of toxic mold is a home that has been empty for months with water damage and no air circulation, or a basement with a leaky pipe that hasn’t been fixed or looked at in months.

Protecting Your Home and Family From Toxic Mold

Mold can grow undetected in a home’s basement or crawl space, inside walls, and underneath furniture and bathroom cabinets. The best way to protect your home against mold growth is by reducing moisture in these key areas and by cleaning up standing water or water-damaged materials quickly.

Reduce moisture in the home by:

Waterproofing and encapsulating crawl spaces and sealing the basement.

  • Running an air conditioner and installing a dehumidifier.
  • Drying wet areas and furnishings immediately after a leak or moisture collects.
  • Removing carpet from bathrooms or unfinished basements.
  • Installing a fan in the basement to improve air circulation.
  • Checking indoor plants for overwatering.
  • Cleaning vents and replacing air filters to improve circulation.
  • Covering pipes with insulation and checking crawl spaces and pipes for buildup regularly.
  • Cleaning bathrooms and kitchens often and removing standing water immediately.
  • Cleaning gutters regularly and directing water flow away from exterior walls.
  • Moving sprinklers away from exterior walls to reduce water buildup.

How to Remove Mold Growth Effectively

If you do find mold growing inside the home, its best to remove it completely and immediately. This means throwing away any spoiled food items and cleaning mold from walls, carpets, and furnishings using professional cleaning products. It’s important not to just caulk or paint over mold in the bathroom, kitchen, or basement. It should be fully removed and the area dried and cleaned first.

Finally, after you remove mold growth, it’s important to fix the problem that caused it to grow indoors immediately. If you don’t, the mold will just grow back. To find a professional to help waterproof your basement or crawl space, install dehumidifiers, or recommend professional mold removal products, please contact your local Groundworks basement waterproofing, foundation repair, and crawl space repair experts to learn how you can protect your home and your family.

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