Avoid Mildew-Keep it Clean and Dry


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Normal weather patterns in Florida include afternoon rains that keep humidity high. Humidity causes mildew to thrive outside; spores are being produced by the zillions. Even if the indoor mildew spore level was low this spring, spores from outside come in on our clothing and hair. Every time windows or doors are opened, in come more spores. Some people are allergic to mildew spores; these allergies are sometimes triggered by continual exposure to the spores. With mildew spores always ready to grow in our homes, what protection is needed to stop mildew from growing and spreading? The watch words are CLEAN and DRY.


  • Mildew must have nutrients to grow. The sources of mildew nutrients are many. Any food spills on carpets, smears on door sills from sticky or oily fingers, soap build-up on shower walls, dirt on clothes, dust on air conditioner filters, the drain pan under a refrigerator, even the air conditioning ducts that channel air to each room can be hot spots for mildew to grow. The first step in avoiding mildew is to plan a program to keep surfaces clean - a regular routine. How often specific cleaning jobs need to be done may be different for each family, depending on the family's lifestyle. Here are some general guidelines in your anti-mildew campaign.
  • Don't let bathrooms become mildew gardens. That means regular cleaning before mildew is visible. By the time mildew is visible, it has produced enough spores to contaminate your whole house. The air conditioning will transplant these spores to other areas of the house.
  • Change air conditioner filters frequently. Once a month may be frequently enough for many households, but, if there are children or pets in the family, check more frequently.
  • Check the drip pan under your frost-free refrigerator and freezer. Dust and dampness there can produce enough mildew and spores to contaminate all the air in your home.
  • Wipe up spills as they occur. Clean carpet spills and spots quickly and thoroughly. Mildew thrives in the cozy carpet pile. Vacuum regularly. Dust and dirt, good mildew nutrients, are harder to remove after they work into the pile.
  • Wash off finger marks on door sills. Even a slight oily residue on wooden, metal or plastic chair arms where hands touch can get slimy with mildew under severe conditions.
  • Don't let dirty laundry pile up. Soiled clothes and towels, mildew quickly when conditions are right.
  • Don't put sweaty clothes into closets. The small amount of moisture they hold will make your closet smell stale and musty.
  • Once shoes have been worn, they are "conditioned" to grow mildew. Perspiration, plus the composition of leather in shoes or belts, is yummy for mildew. Let sweaty shoes dry before putting them away in your closet.


  • Mildew needs moisture to grow. The big question is, "How can you keep a home in warm, humid Florida dry?" Air conditioning removes moisture from air, but if moisture comes into a house faster than air conditioning can remove it, mildew will show up and it will spread. Air conditioning can usually remove the moisture produced inside a home through cooking, cleaning, bathing and other water-related activities. The moisture we need to be most concerned about in Florida's warm and humid climate comes into a house from outside in one of several ways. Here are several guidelines to cut down or prevent moisture from coming into a home.
  • Every time people open outside doors to come and go, moisture moves inside. People must be free to come and go, but it will help reduce moisture if they open and close doors promptly.
  • Air enters homes through cracks and crevices. Look around windows and doors. If you can see daylight anywhere, that is an invitation to moisture you can stop with weather stripping. See your friendly hardware store for the right type of weather stripping for your window or door types.
  • Hold a lighted match in front of each electrical outlet. If the flame flickers, moist air can leak in. There are inserts to put behind cover plates to control air and moisture leakage.
  • A fireplace has a large opening that air and moisture can come through. Make sure the damper (and glass doors, if present) are closed.
  • Check the air conditioning and ducts in your garage. Are there cracks in joints where garage air and moisture can get into the system? Use duct tape and/or caulking, depending on the type and location of the crack. Moisture coming into the air conditioning system through joints and cracks in duct work are often the biggest source of moisture where severe mildew problems are found.
  • Bath and kitchen exhaust fans remove moisture and odors from those rooms. That's good. But, they also create a negative pressure in a house that pulls warm, humid outside air into other parts of the house. That's not so good. Usually a bath fan can remove most of the excess moisture put into the air during showering or bathing in about 10 minutes. Wet towels and wet walls will continue to put moisture into a bathroom for hours, but long fan operation can bring in more moisture than it removes. To reduce moisture that wet walls and towels contribute to your home over the next few hours, use a squeegee or the towel you dried with to wipe down wet shower walls. Then, put towels on a rack in the garage or on the porch
  • Finally. When the temperature of outside air drops to the low 70's during the late evening, should air conditioning be turned off and windows opened to save energy? The answer is NO, not in Florida. That outside air is saturated and will bring a lot of moisture. When air conditioning is turned on again the next day, it will have to work harder to remove the excess moisture. During this period, moisture will be high enough to invite mildew.

Keeping your home mildew-safe during warm, humid weather requires a routine that is not difficult, but requires team effort. Call a family council. What can each person do to help keep your home clean and dry to avoid the hard work of cleaning mildew, the costs of repairing and repainting after mildew damage to a home and its furnishings and the bad effects of long-term exposure to mildew spores?