Air Quality Testing & Environmental Services

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What are the signs / causes of mold contamination?

mold-leakThere are many clues to look for when attempting to identify a mold contamination issue in your home.

Out of the various signs of systemic mold contamination, a list is as follows:

  • Musty Odors
  • Visible Mold Growth
  • Signs Of Water Intrusion
  • Past Flooding
  • Condensation / High Humidity
  • Health Related Issues

Issues with mold are easier to predict when multiple signs of mold growth are present.


Musty Odors

Even though mold may not always be visible to a homeowner, smell permeating from active mold growth is almost always noticeable. Mold growth behind walls, in attics, behind wallpaper, or under paneling will permeate an odor if active.

If you smell a musty smell in your home, it is best to secure a mold assessment form a certified environmental specialist to evaluate the presence of airborne mold spores. Early detection will limit any existing damage to your residence as well as protect your family from inhalation of dangerous mold.


Visible Mold Growth In More Than One Area

Visible mold growth in as little as one area of your home will be enough to warrant a professional mold assessment to determine the extent of your mold contamination issue. Discolorations in drywall, wood, or concrete appearing as dirt or other debris should be investigated further.

Mold may not always be black; other common colors include red, pink, green, white, tan, and more. Mold can be mostly any color depending on the type or strain you are dealing with. If the area in question is in doubt, a simple laboratory test can identify with certainty if the mold in question is really mold.


Signs Of Water Intrusion

As water makes its way into the house, almost always does it become a future problem for the homeowner. Grading problems around the home are one common way water enters the home as is clogged gutters which allow rain water to enter cracks in the homes foundation. Leaking pipes are another common source of water intrusion in the home leading to mold contamination in almost every case.

If you notice a spotty discoloration in your home’s walls, ceilings, or floors, you most likely are experiencing water intrusion. Water stains of this type should provide cause to believe mold is forming on the other side of the stain in question.

Another sign of water intrusion would be bubbling, peeling, or cracking of your homes paint or wallpaper. Water soaked building materials will either bulge in or out as they lose their original structural integrity. If these potential problematic materials are moist to the touch, you will know that your relative mold risk is high.


Past Flooding

If your home has flooded in the past year, there is a high chance you have some mold growth as a result— especially if the property was not properly restored soon after the flood. Water soaked drywall or wood will not usually dry out quick enough to prevent mold growth from occurring. Basements are the typical culprits for obvious reasons and will have mold growing everywhere water has reached including cinder blocks that line unfinished basements.



High humidity in the home will lead to condensation formation on the walls, pipes, and on the windows of a property. Moisture in the air will not usually form condensation on surface materials until humidity levels raise above 70% RH. Any amount of condensation in the home should be taken as a sign of mold growth as mold thrives in a humid environment.

Standing water anywhere in the home will almost certainly raise your humidity levels as will improper ventilation in the home’s bathrooms. A home without proper air conditioning can also create issues with humidity over time. Check for structural problems in your home when humidity levels rise to unacceptable levels or consult with an environmental specialist to receive advice on how to do this properly.

Posted in: Mold