Mold Remediation: All About the Basics and Process for Removal

A basement in the midst of construction

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Mold remediation helps homeowners and residents stay safe by identifying large-scale mold within the home and eradicating or encapsulating it. Mold remediation has also increasingly become a frequent component of selling and buying a house. Because of the critical nature of types of mold, some operators can take advantage of homeowners. Is mold remediation a genuine, worthwhile project or just a big scam?

The Basics of Mold Within the Home

Mold is a familiar condition in many homes. Wetter areas of the country have moldier homes, and even homes in dry areas have certain rooms and spaces that are more prone to developing mold.

Where there is moisture in a home, there is undoubtedly mold. The most familiar example of mold is the type that develops in the grout between ceramic tiles. A simple form of homeowner-driven mold remediation happens each time you spray that mold down with a bleach-based cleaner and wipe it off. More critical mold, either from a safety or aesthetic standpoint, happens elsewhere.


Just crawl in the ceiling above your bathroom and you will likely find mold. Some mold, but not all, produces health-threatening mycotoxins. Not everyone is affected by mold, but people who are affected are often gravely affected. Aesthetically, mold is never a good thing. In visible areas, mold signifies neglect and decay. Functionally, mold can reduce the effectiveness of insulation.

Areas of the Home That Develop Mold

All places where water is found can develop mold. An excessive amount of humidity in a house can condense and cause mold. Ironically, newer homes can often experience more mold growth than older homes because they are more tightly insulated. Fiberglass insulation provides fertile ground for mold growth and makes it difficult to eradicate and remove.

  • Attics
  • Crawl spaces
  • Wall interiors
  • Basements
  • Around chimneys
  • Furnaces
  • Ducts
  • Kitchens
  • Under sinks
  • Near foundation air vents
  • Under window unit air conditioners

The Process of Mold Remediation

The Environmental Protection Agency (EPA) notes that any moldy areas less than 10 square feet (about 3 feet by 3 feet) can be remediated by the homeowner. Beyond that, you may want to talk to a mold remediation contractor. In most cases, it is better to have a mold remediation contractor do the work than a general contractor.

Even though chlorine bleach is often used to kill mold, bleach is not an EPA-approved biocide. For that, you will need to use a product such as Mold Stat. If a space with 3 feet by 3 feet of mold growth is heavily concentrated or near the HVAC system, it should be contained to prevent dispersal.

Containment and Ventilation

The first step, and arguably the most important, is setting up containment and ventilation. The use of proper ventilation and air filtration devices (AFDs) such as air scrubbers is required to ensure that mold spores that are disturbed and become airborne are not spreading to an uninfected area.

Cleaning and Disinfection

Cleaning and disinfecting is the next step, and this is the stage that includes the actual remediation and disposal of infected materials. After the cleaning and disinfecting, the technicians apply biocide/fungicide/moldicide solutions.

Fix the Mold Source

The next step is where the technicians address any moisture or humidity concerns. For example, if a loose bathroom fan duct is running into an attic, the fan duct may be fixed. If the fix is easy, the mold remediation company may take on the repair by itself. For more involved repairs, the company may hire a sub-contractor or recommend one for the homeowner.

Encapsulate the Mold

Mold that has not been removed can be encapsulated by paint or a similar material. Encapsulation is an approved method of dealing with mold in a home, though it is only an approved method when most of the mold is removed and the affected area is totally dry. The source or cause of the mold should be fixed prior to painting or caulking. Encapsulating wet active mold sources is not an approved method.

Not All Mold Is Toxic Mold

According to the Centers for Disease Control: "While certain molds are toxigenic, meaning they can produce toxins (specifically mycotoxins), the molds themselves are not toxic, or poisonous." And while it is possible for toxigenic molds to produce rare health conditions such as pulmonary hemorrhage or memory loss, this rarely happens.

This is not to say that mold cannot produce health issues. People should be educated with a clear understanding of the risks of mold, but not made to panic or caused undue alarm.

When to Call a Professional

Mold remediation companies certainly do good work when the mold is widespread and is in a public institution or in commercial buildings. While most mold is not toxic, some mold can be hazardous. For this, you want a licensed, experienced professional dealing with the mold.

Mold problems that we see today are problems that we unknowingly created ourselves, and they are not problems we had only a few decades ago. Since the mid- to late-1970s, federal requirements have directed that homes become more energy-efficient. The more energy-efficient the home, the tighter that home is sealed, and the less natural breathability the home has.

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  1. Mold. Centers for Disease Control and Prevention

  2. Mycotoxins Fact Sheet. World Health Organization.

  3. Mold Remediation Guidance. National Institute of Environmental Health Sciences

  4. Mold Cleanup in Your Home. United States Environmental Protection Agency

  5. Should I Use Bleach to Clean Up Mold? United States Environmental Protection Agency

  6. Basic Facts About Mold and Dampness. Centers for Disease Control and Prevention

  7. Mold. Centers for Disease Control and Prevention

  8. Air Sealing Your Home. U.S. Department of Energy