Mold in Your Attic Near Charleston, Lexington, Georgetown

Step #1: Know Your Enemy

Molds belong to a vast family of fungi that can grow just about anywhere if moisture, oxygen and cellulose (or other organic material) are present. Because mold reproduces by microscopic spores that travel in the air, it can easily find its way into the attic through roof vents, air leaks in the attic floor and larger openings like attic hatchways or drop-down stairs.

Airborne mold spores cause a wide range of respiratory ailments and allergic reactions. But when mold is found in the attic, the main concern is usually damage from rot and excess moisture. It’s not important whether you see black mold in the attic, white mold, or another color. The issue is how to stop mold from spreading and causing more severe damage.

Moist Air in a Cold Attic Promotes Mold Growth

Attic mold is more prevalent in colder climates than in warm climates. To understand how an attic mold infestation can start, let’s look at some common ventilation errors. In many houses, a bathroom vent fan is allowed to dump moist bathroom air into the attic space rather than ducting this air to the outside. So when someone turns on the bathroom fan while taking a hot shower on a cold morning, a large volume of warm, moist air is blown into the attic space. When the warm, moist air hits cold roof sheathing in the attic, most of the moisture condenses out of the bathroom air. Water wets the roof sheathing, drips down the rafters and saturates attic insulation. Wet wood in a dark space is an ideal environment for mold to take hold.

Attic Mold Also Indicates Energy Problems

Warm, moist air that makes its way into a cool attic causes more than attic mold problems. In many houses, it’s also a sign that too much conditioned air is leaking into the attic, compromising comfort and causing the HVAC system to consume more energy than necessary.

Warm, moist air from the living space doesn’t need a fan to migrate up into the attic. It can get there through air leaks –around recessed light fixtures, through gaps around heating vents, through air leaks around an attic access hatch, and through numerous other cracks and leaks. Mold can form in the attic from this “passive” air leakage alone.