Just How Common is Interior Household Mold?

In recent years, the dangers of interior mold have become more and more known, and federal agencies including the Centers for Disease Control have warned residents against the risks of living in a home with mold. Complications that can result from mold include triggered allergy and asthma symptoms, respiratory problems and sinus infections. Despite the level of awareness being raised on the issue, you may be wondering, just how common is mold?

How Many Homes and People are Affected by Mold?

Unfortunately there’s no answer for how many homes and buildings have mold, but it’s estimated to be in the millions. Mold can be found in homes in any region of the U.S., although it does seem to thrive best in humid, warm conditions, but it can also survive in dry, cold climates. An estimate of homes with mold may not be available, but it is believed that about 5% of the population has allergic symptoms related to inhaling mold. Another reason it’s difficult to gain an estimate on mold in homes is because in reality, mold is present everywhere, both indoors and outdoors, but there are particular types of mold that are toxic. Mold also becomes more problematic when there’s large amounts of it located within a home. It’s not just residential homes that are at risk for mold. Mold can appear in any building where there’s moisture, and that includes office buildings and apartment buildings. The most common strains of indoor molds are Cladosporium, Penicillium, Aspergillus, and Alternaria.

How Mold Enters a Home

Mold spores are naturally occurring outdoors, but they can enter a home through windows, doorways or any other entry point or open area in a home. They can also be carried indoors on animals, shoes and clothing. While the presence of natural mold spores isn’t necessarily a problem, the problem comes into play when there’s excessive moisture in a home that can serve as a breeding ground for these spores. For example, when there’s flooding, humidity or standing water in a home, there’s an increased likelihood that the normal levels of mold will become problematic.

Top Cities in the U.S. For Mold

In 2011, there was a survey done of the cities with the highest presence of mold and mold-related allergies. The cities that topped the list included:

  • Dallas: Texas as a whole has a long-standing history of dealing with mold problems. In fact, a Texas resident sued her insurance company in 2001 because of mold-related illnesses and received at $32 million settlement.

  • Phoenix: This one may surprise many people, because it’s such a dry environment, but many southwestern states rank high in terms of allergies and mold-related problems.

  • Chicago: The Windy City makes the list because the Midwest is known for allergens, but also the city is located on the shores of Lake Michigan, and also receives lots of snow and rain, making it the perfect environment for mold.

  • Other areas that ranked on the list include Riverside-San Bernardino and Los Angeles.

Regardless of the region of the country that you live in, mold can strike and can have serious health consequences. Aside from health-related concerns, mold can also lower the value of a home and cause structural damage. It’s important that if you’ve experienced flooding, or suspect mold is present in your home, that you contact a mold remediation specialist such as Best Dry Flood and Mold Specialists, Inc. to handle the problem effectively.

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