What Causes Mold in Your House?

Finding mold in your house is never fun, but what causes it? Mold is a fungus and is present everywhere around us, as it needs oxygen and moisture to survive and grow. The leading cause of mold in your house is an excess of moisture, which is why mold is commonly found between walls, under sinks, in basements and crawl spaces, and in other areas of the home near water and with low ventilation. 

Most mold is easy to eradicate, but it’s always easier to fend it off than to remove it. Dehumidifiers can help, but understanding this unwanted growth—and taking measures to prevent it—will go a long way in ensuring a mold-free home. 

Due to the health risks involved, it’s imperative to call a professional if you see mold, suspect its presence, or have unexplained health complications.  

Types of Mold

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Allergenic 

Allergenic mold, as you have probably guessed, is mold that is known to cause allergic symptoms. These symptoms usually show in the form of sneezing, a runny nose, skin irritation, and light coughing. Allergenic molds are the least dangerous of the three types, but when left untreated can grow quickly and cause significant long-term health issues. 

Pathogenic

Pathogenic molds in your home are more serious than allergenic and can cause infections, especially in people with compromised immune systems. Unlike a minor cough or runny nose that is characteristic of allergenic mold, pathogenic molds can cause more serious issues like pneumonia, fatigue, and neurological issues. 

Toxigenic

Toxigenic mold is toxic, made even more serious by the fact that unless you are an untrained mold professional, it’s hard to tell the difference between the three types listed here. Toxigenic mold—like Stachybotrys, or black mold—produces mycotoxins that are almost guaranteed to cause serious health issues. Call a local mold professional immediately if you see any mold even resembling black mold. 

What Causes Mold 

Mold is caused by a number of factors. Any one of the below causes can encourage mold growth, but in reality, it’s usually a combination of two or three. Some common causes include:

• Poor ventilation

• Water leaks and water damage 

• High humidity

• Condensation, especially in the colder months

• Damp materials left sitting

• Increase in moisture from activities like showering, cooking, etc.

• Location and climate 

Mold cannot grow in a dry environment as it feeds on water to grow. Controlling humidity is the number one way to combat mold growth in your home.  

How to Prevent House Mold

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Preventing mold is something that needs to be considered at least seasonally if not monthly or even weekly. Mold grows very easily, but the good news is you can usually keep it to a minimum if you take preventative measures.

Dehumidifier

A dehumidifier works great at keeping a room’s relative humidity within a normal range. It’s most effective when placed in spaces where it can remove the most moisture, especially areas with low ventilation. This is why you often see dehumidifiers in basements, bathrooms, and other rooms where you may not have a fan, but have increased moisture, as dehumidifiers are great at preventing mold. 

Air Purifier

An air purifier by itself won’t control humidity—while some can, they’re expensive—but an air purifier helps remove harmful particles in the air. Those with compromised immune systems should consider an air purifier in their house or, at the very least, in their bedrooms. Some HVAC systems will have dehumidifiers and air purifiers installed, and that’s really the best option (but also the most pricey).

Ventilation

Proper ventilation is key to preventing mold. Sometimes all you need is to place a fan in a high-traffic area, or a fan pointed out of the window in order to move air from the room to the outdoors. Flipping on a bathroom fan when showering or bathing helps keep humidity in check. 

Clean Surfaces

Mold is a particle that exists in the air, which also means it settles on surfaces. While it isn’t realistic to wipe down every wall and ceiling on a regular basis, keeping surfaces clean can prevent or even kill mold particles. 

Monitor Humidity

Remember we said prevention is better than fixing an existing mold problem? Humans aren’t great at guessing humidity levels, so buying an inexpensive thermometer/hygrometer combo and placing one in a few of your rooms—especially basements—is a great way to measure humidity in your home. Remember, the sweet spot is 25-50% relative humidity. 

How to Remove House Mold

Removing mold yourself is something that you should reconsider. Once mold is seen it has already spread. It’s extremely easy to disturb, causing it to go airborne and impact your health. We strongly recommend having a professional handle all mold problems, but there are some ways you can tackle small mold spots on your own. 

1. Wear heavy protective gear over eyes and airways. 

2. Investigate and locate the mold source. 

3. Use powerful antimicrobial sprays. Another alternative is a bleach and water mix. 

4. Ventilate thoroughly for at least 24 hours after removing the mold. 

5. If you have one, dehumidify the room after ventilation.

Knowing which mold you should and shouldn’t tackle on your own, however, is extremely difficult. Mold test kits are often unreliable and it’s hard to tell the difference between toxic and allergenic mold on sight alone. A professional may seem expensive, but mold is one of those things where it’s best to spend money to make sure it’s done right—both for your home, and your health.