Air Conditioning and Mold

The way we build homes has changed enormously over the past 100 years. In the past, I have written about how plumbing has fundamentally changed the relationship people have with their homes. Today I will be discussing the way that air conditioning has changed the way we live, and our relationship with mold.

It would be difficult to overstate the impact that air conditioning has had on our society. Throughout history, many people have migrated with the change of temperatures. Nomadic tribes migrated north for the summer and south for the winter. In the 18th and 19th centuries, it was very common for Charleston families to migrate to the upstate of South Carolina. The city of Asheville, North Carolina became a popular resort destination in large part because it was comparatively cool in summer.

One of the best known stories of temperature migration is the film, “The Seven Year Itch.” In this film, a mild mannered married businessman is tempted by the beautiful Marilynn Monroe. Many people remember the very suggestive photos taken of Monroe wearing a white dress. Most people forget the reason why the mild mannered businessman had the time to be walking with Monroe in the first place. His wife had taken his child to the country for the summer because the city was just too hot!

Air conditioning fundamentally changed the dynamics and necessity of temperature migration. It was no longer necessary to move north or out of the city for the summer. You only needed to turn down the thermostat. In Charleston, the outside temperatures often climb over 100 degrees. But as long as you stay indoors, it is quite bearable.

While air conditioning has made our homes and offices far more comfortable, it has also made them more susceptible to mold. Water moves from a gaseous to a liquid state when the temperature drops to dew point. Since air conditioning cools the air, it introduces many opportunities to produce condensation. In a well-designed, properly installed system, this condensation should occur just above the drip pan.

Unfortunately, not all systems are well designed or properly installed. Some systems are oversized. Some duct work is improperly insulated. Often they are not hung, but simply sit on sheet rock ceilings. Some vents are unsealed. All of these issues can cause water to reach dew point in unintended places.

This is an open invitation to mold growth. When a system is oversized, mold can easily grow inside the air handler and duct work. Every time the HVAC system is engaged, it is spreading mold spores throughout the home.

Improper insulation of duct work can cause condensation inside a crawl space. Mold spores can migrate from the crawlspace to the home’s interior. Ironically, this issue has been complicated by energy conservation. Over the past several decades we have been building houses whose walls and windows are far better insulated. This has greatly reduced utility bills.

Unfortunately, when the HVAC system is engaged it is much less likely to pull air from the outside environment. Instead, the HVAC system is much more likely to draw air from the crawl space.

One of the most common sites for mold growth is around the air supply vents. When these are improperly sealed, water will condensate on the sheet rock around the perimeter of the vents.

Air conditioning has dramatically improved our lives. It has also made us more susceptible to mold.

Whenever you find mold in your home, call Rainbow International. We perform mold removal services in Charleston, North Charleston, Mt. Pleasant, James Island, Johns Island, Folly Beach, Kiawah Island, Seabrook Island, Sullivan’s Island and the Isle of Palms.