Mold and mildew growth require several elements for idea growth — a source of food, warm temperatures and adequate moisture. Of those three, the presence of moisture is the most critical. Unfortunately, controlling the environment in your home can be tough.
Rainwater can enter a building through leaks in walls, windows or the roof. Surface or ground water may enter when there is poor foundation drainage. Flooding can, of course, cause catastrophic intrusion. In buildings that have slab construction, water can seep or wick up through the cement floor causing mold to grow on carpet pads or carpet backing. The building envelope (walls, windows, floors , roof , etc.) must be well maintained to prevent water from coming in, both to prevent mold growth and to maintain the structural integrity of the building.
The summer months and summer storms can cause relative humidity to soar both outdoors and inside your home. When the relative humidity inside your home becomes elevated, building materials and furnishings absorb the moisture. Those damp materials can then provide a good place for mold to grow. If the relative humidity in a home stays above 70 percent for extended periods of time, mold will almost certainly grow.
However, humidity isn’t the only thing that can cause moisture in your home. Clothes dryers, bathrooms and kitchen can put a tremendous about of water vapor into the air. All three should be properly vented to the outdoors. Bathroom exhaust fan should be in use whenever the shower or bath is running. A properly vented kitchen exhaust fan can remove steam created during cooking.