Mold in Attics

Mold can form in attics for many reasons, and because attics are generally not often visited by homeowners, mold problems can develop without the homeowners’ knowledge and can be quite established before discovered.  Some of the reasons mold occurs within attics are discussed below.


Condensation can occur in attics during winter as warm household air meets the cold roof.  Attics with good ventilation allow this warm household air to escape but, if the space is poorly ventilated, the warm air against the cold underside of the roof will condense and cause moisture to bead. This is the same phenomena as occurs when a cold drink sits on the table in a warm room. As this attic moisture drips onto insulation or down behind walls, mold can form and grow, causing significant damage before it is discovered.

Mold can also form in the attic and walls if the roof leaks.  Attics should be visited on a regular basis – and during heavy rains – to monitor roof integrity and note any leaks before a problem occurs.

Many homes have bathrooms vented into the attic space rather than out through the roof. The humidity from this improper ventilation may also cause mold.  Forced air ductwork and the exhaust from dryer vents are also often found to be the sources of high attic humidity.

As with mold anywhere else in the home, it must be remembered that mold reproduces by spores in the air.  Additionally, even when cleaned from the surface, mold on porous materials such as wood generally grows “roots” that can re-grow the mold in a relatively short period of time.  Chemicals used to kill mold must also kill the roots.

If attic insulation is found to be moldy, it should be removed and replaced.  Mold needs moisture and a food supply.  And mold’s favorite indoor buffet includes the wood, drywall, insulation, and textiles found in homes.

Although there are some forms of mold that are black and toxic, not all mold s that are black are toxic. Mold can be tested to determine which form is present in the house.

When do-it-yourself attempts are not enough, or when mold is suspected within walls, the best thing to do is to contact a professional mold remediation company.  These trained technicians can also assist homeowners with recommendations for lowering the humidity in the attic after mold removal is compete to keep that mold from returning.

24/7 Call Now: 1-888-681-1071