What To Know About Household Mold
Household molds can cause allergic reactions and severe health effects in people who are immunocompromised. Learn how to identify and prevent mold growth in your home.
No one wants to clear out of their home due to mold remediation, yet this happens to millions of American households annually. The U.S. Census Bureau 2019 American Housing Survey found that 3.7 million homes reported mold within the previous 12 months. We investigated common types of mold, symptoms of mold exposure, and the cost of mold remediation to help you prevent its growth in your home.
Key Findings
- According to U.S. Census Bureau 2021 American Housing Survey data, more than 1.6 million households reported mold in their homes in the prior year.
- Aspergillus, Cladosporium, and Penicillium are the three most common types of indoor mold.
- Professional mold remediation costs an average of $3,500 and ranges from $10 to $30 per square foot.
- Reducing indoor humidity levels to between 30% and 60%, controlling moisture, and increasing ventilation can help prevent additional mold growth.
Different Types of Mold
Aspergillus, Cladosporium, and Penicillium are the three most common types of household mold. The table below illustrates various types of mold and their defining features:
| Mold Type | Distinguishing Characteristics |
|---|---|
| Alternaria | Coming into contact with this black or grayish mold can cause hay fever-like symptoms. |
| Aspergillus | Responsible for respiratory infections, food contamination, and skin irritation, Aspergillus can also lead to pneumonia or aspergillosis. |
| Aureobasidium | Despite its slow growth, Aureobasidium can cause respiratory system issues and costs more to remove than most indoor molds. |
| Chaetomium | Fuzzy and black, Chaetomium can cause allergic reactions and even attack the central nervous system in people with weak immune systems. |
| Cladosporium | Moldy smells are often attributed to Cladosporium, one of the most common indoor molds. |
| Fusarium | Quick to spread, Fusarium is typically harmless but can cause severe infections in people who are immunocompromised. |
| Penicillium | Some forms of Penicillium are responsible for penicillin, while others integrate into the cheesemaking process. Removing this rapidly spreading mold from your home requires more effort than removing other types of indoor mold. |
| Serpula lacrymans | Typically wood-inhabiting, Serpula lacrymans mold rapidly deteriorates wooden structures. |
| Stachybotrys chartarum | Otherwise known as “black mold,” Stachybotrys chartarum commonly grows in water-damaged buildings. |
| Trichoderma | Trichoderma blooms white but then turns from yellowish-green to green. It’s often sweet-smelling. |
| Ulocladium | Infected plants and spoiled food can carry Ulocladium, which costs more than the average household mold to remove. |
How To Identify Black Mold
Stachybotrys chartarum, or “black mold,” gives off a musty smell and may appear either gray, greenish-black, or brown. Most black molds thrive near sources of water or condensation. Along with areas of high moisture, black mold flourishes around fiberboard, paper, and drywall.
Black mold spores appear in groupings that spread out from a central location. Lighter patches of black mold indicate that spores are beginning to take hold, while darker spots signal a larger presence. Along with its characteristic color, black mold can look slimy, powdery, or furry to the naked eye.
Symptoms of Mold Exposure
The Centers for Disease Control and Prevention (CDC) reports that fungal diseases prompt more than 75,000 hospitalizations annually. Reactions to mold can manifest immediately or appear long after exposure. Hidden mold growing in ceiling tiles, ductwork, drywall, wallpaper, paneling, or carpet padding can induce health effects similar to visible mold.
Allergic Reactions
Mold can cause allergic reactions in people regardless of their sensitivity to mold exposure. Typical reactions include sneezing, a runny nose, or nose irritation. Airborne or physical contact with mold can also result in red eyes and skin rashes.
Respiratory Complaints
Irritation of the throat and lungs can signal mold exposure. Individuals with asthma may have trouble breathing due to mold spores.
Serious Illness
People with susceptible immune systems may develop serious illnesses due to mold exposure. Hypersensitivity pneumonitis, characterized by inflammation of the lungs, can appear with pneumonia-like symptoms such as shortness of breath, muscle aches, and severe fatigue. Inflamed lungs, wheezing, coughing, and chest tightness may also indicate bronchopulmonary aspergillosis.
Cost of Mold Remediation
The cost of mold remediation generally ranges from $10–$30 per square foot. Professional remediation typically costs $1,500–$9,000, with an average bill of $3,500. However, the most extensive mold remediation projects can cost tens of thousands of dollars.
The Environmental Protection Agency (EPA) says that you can typically remediate moldy areas smaller than 10 square feet with detergent, water, and some elbow grease. Large-scale mold infestations require a professional approach, however. Factors that influence the final cost of mold remediation include the following:
- Duration of removal: The more extensive the removal process, the more labor is required to complete the remediation process.
- Mold location: The more difficult it is to access, the higher your bill.
- Size of the affected area: The more square footage affected, the higher the labor costs.
Mold infestations can also incur additional costs after remediation, namely replacement materials such as carpeting, hardwood flooring, and drywall. Foundation repair costs can also increase your final bill if structural cracks allow moisture to seep in. The 2021 American Housing Survey found that nearly 5.8 million homes had leakage inside the structure, and more than 7.5 million had leakage from outside of it.
Cost data sourced from Fixr.
How To Prevent Mold
Immediate action and cleaning can help prevent mold from spreading or occurring in the first place. If you encounter plumbing or water leaks, fix them immediately. Dry out any affected objects or areas and dispose of absorbent or porous materials to prevent mold growth. Renters should immediately notify their landlords of any water issues.
Reduce Humidity Levels
Preventing indoor humidity levels from exceeding 60% can deter mold growth. Run the air conditioning system to lower the temperature in your home or apartment and invest in a dehumidifier.
Increase Airflow
Proper ventilation can also decrease humidity and reduce the potential for mold. Turn on exhaust fans when cleaning, cooking, or dishwashing. Insulate pipes to decrease the chances of condensation forming and promoting mold growth.
Invest in Appropriate Building Materials
Local climate and soil types heavily influence the building materials common in a particular geographical area. For example, fewer houses in the South have basements due to damp soil caused by a higher water table. When building or repairing your home, consider which materials to incorporate to deter mold in your basement, such as installing vinyl versus carpeting.
Our Conclusion
The physical and financial toll of household mold is steep and increases the longer the mold has spread unchecked. If you’re in need of mold remediation, consult your homeowners insurance policy to determine the potential for coverage. Gather estimates from three professional mold remediation specialists and verify their credentials before moving forward.
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