By: - Updated: August 20, 2018


What is mold and how does mold grow?

Before you learn how to prevent mold from invading your home, it is time to understand what mold is and what causes it. Once you understand what causes mold, you will find the best ways to prevent it.

Of course, if you already have mold problems in your house, learning about mold prevention will be a waste of time! Grab your phone instead and call professionals to test it and treat it properly.

Understanding mold is the key to prevention

Just like yeast and mushrooms, mold (or mould) is a type of fungus that grows on plants, wood, fabric, food and any other organic material. Put simply, mold is a natural recycler of dead organic matter. Although it sounds like a nice thing to do for nature, in most cases, it is not a nice thing to do for humans.

Individual mold colonies are very small and impossible to see without a microscope, but once a mold colony emerges, it can form visible spots on special places. Mold usually comes in these colors: black, blue or green. The color of mold is determined by various factors such as type, nutrient source, age of the colony, etc. Of all mold types, black mold (officially called Stachybotrys) is considered to be the most harmful one to the health of living beings.

The type of mold will determine the way of remediation. That said, it is very important to test it first. Knowing what mold type you have to deal with will be helpful even after conducting remediation activities.

Unfortunately, not all mold types are the same, but we can roughly divide them into 3 big types:

  1. Allergenic – this type of mold is the least harmful of all mold types; however, it can cause problems for people who are allergic to mold or have asthma. Allergenic mold is usually not life threatening.
  2. Pathogenic – this type is often harmful, not only for people with asthma or mold allergies, but for healthy people too. For example, this type of mold can cause hypersensitivity pneumonitis, an acute response resembling bacterial pneumonia
  3. Toxigenic mold – this type of mold can actually cause serious health issues, both temporary (eye irritation or cough) and permanent (e.g. immunosuppression, neurological disorders, or cancer). Toxigenic mold produces mycotoxins – a toxic chemical present inside or on the surface of the mold spore, which can be inhaled, ingested or touched.

Now that you know what mold actually is, you should also understand what causes it.

Just like any other living being, mold needs water to grow. As a matter of fact, without water, mold cannot grow at all. Other factors that are crucial for mold growth are food source, oxygen and temperatures between 40 and 100 degrees Fahrenheit.

Does that mean that by removing the main mold growth factors, we can eliminate mold once and for all?

Sadly, the answer is no. It is almost impossible to keep a place mold-free mainly because you cannot eliminate oxygen from a place and actually stay at that place, nor can you build a house without any organic materials such as wood, carpet, plants, etc.

What you can (and should do) is focus on:

  1. Moisture control
  2. Dust control
  3. Proper ventilation of your house


Is it mold or mildew?

Although often considered to be the same thing, mold and mildew are better explained as two brothers with a similar feature. Both of them are frequently seen in homes, especially in moist and warm areas such as food, walls, shower, etc. That’s where the similarity ends.

Mold is a living organism that produces airborne spores and as such has harmful effects on health. Mildew is an accumulation of dirt and grime. It is not a living organism, it will not reproduce and cannot produce harmful mycotoxins, but it can potentially decrease the quality of your life. Unlike mold, which comes in much darker shades, mildew is often white or grey. While mildew is easily treated with a store-bought cleaner and a scrubbing brush, mold often requires a more professional touch.

Just like mold, mildew also requires certain factors to develop and grow. The requirements include a food source, moisture and temperatures between 77 and 88 degrees Fahrenheit.

What impact does mold have on your health?

Everyone’s immune system and medical history is different. That said, most government or medical guidelines abstain from providing safe exposure limits to mold. Due to these variables, it is impossible to say if exposure to low concentrations of mold is safe since every individual will react differently.

The fact is that people with suppressed immune systems are most likely to experience health issues when they spend time in a room filled with mold. Although difficult to predict, exposure to mold growing indoors can be associated with nasal and sinus congestion, cough/sore throat, asthma (or exacerbation of it), nosebleed, headache, skin and eye irritation, etc. Long-term exposure to indoor mold can lead to health issues which develop faster for certain groups – infants, children and elderly people.

It is very important to keep in mind that some types of mold are capable of producing extremely potent toxins called mycotoxins, which can lead to severe health consequences such as cancer.