Mold vs Mildew – What’s the difference?

Do you know the difference between mold and mildew?

To most people, they’re both just fungi growing in their homes or businesses that they want to remove immediately! While immediate removal is certainly the best idea, we thought we would educate you a bit on their differences! The two are very similar fungi, but also very different – from appearance to health hazards, we’ll explain the major differences between the two.


Mold is a fungi that is fuzzy in appearance and can be a variety of colors – blue, green, yellow, brown, gray, or black. Some mold may even be described as hairy. Although mold may resemble mildew, mold often appears to be a darker, deeper color.

Not only can mold cause damage to your home or business, but you can also develop severe health problems as a result of mold growth. Extremely dangerous toxins can begin to develop, resulting in black mold. Black mold will result in extreme health complications for you, your family, coworkers, tenants, patients, etc. Symptoms that can occur from mold growing in your surroundings are the following:

  • Difficulty breathing
  • Coughing
  • Sneezing
  • Sore throat
  • Migraines
  • Sinus infection
  • Pneumonia
  • Allergic reaction
  • Rashes or hives
  • Inflammation
  • Extreme fatigue


Mildew is also a fungi, but it grows in a flat pattern and may appear to be powdery. It can start by looking white, grey, or yellow, and later turn black or brown. Another indication that mildew is present is a musty smell in the air.

Damage from mildew can occur on paper, leather, fabrics, and walls, and will also affect your health. Fortunately, the health risks are minor compared to the health risks that accompany mold. If you’re in the presence of mildew, these are some common symptoms that may affect you or those around you:

  • Difficulty breathing
  • Coughing
  • Sore throat
  • Headaches


Mold and mildew thrive in moist conditions, therefore the best thing you can do to prevent the growth of mold and mildew is to keep your home or facility dry and moisture-free. If you’re building a humidifier, check the humidity level and take action to control it – high levels of humidity result in the potential growth of fungi. You can also control humidity levels with a dehumidifier, which will remove excess moisture from the air.

Check your bathroom, kitchen, or other areas for leaks. If you have a leaky pipe, it will cause excess moisture to collect, which is a great source for mold and mildew to grow. Don’t forget about your windows, either! Inspect your windows to ensure they are sealed properly and do not allow water to seep in.


When cleaning/removing mold or mildew from your home or business, we recommend contacting a professional. Oftentimes residents will use a bleach solution to remove the fungi. While bleach will kill the fungi, it will only kill the surface layer of the fungi. Mold and mildew can grow on many surfaces, but they will more commonly develop deep inside a porous surface. Therefore, in order to kill all of the fungi you would need to ensure the bleach solution reaches the deepest part of the porous material. Even then, a spot can be missed resulting in the fungi growing back stronger and faster, making it more difficult to manage.

For more information about mold remediation, click here.