10 Tips to Prevent Mold in Your Home

Fixing mold damage is an expensive and time-consuming home repair. But you can save time and money with these 10 tips to prevent mold.

Homeowners have good reason to shudder when hearing, “You’ve got mold!” Mold can wreck your health and your finances: An extensive mold remediation can reach five figures. Here are 10 ways to prevent, control, and combat mold in your home.

1. Eliminate Clutter. Cast a critical eye on household clutter, and pare down your stuff. Clutter blocks airflow and prevents your HVAC system from circulating air. Furniture and draperies that block supply grilles cause condensation. All this moisture creates microclimates in your home that welcome and feed mold growth. So throw out things you don’t love or don’t use. Push furniture away from vents and grilles to keep air circulating. On humid, still, days, run a couple of fans to keep air moving.
2. Control Indoor Climate. Mold problems often emerge during hot, humid summers when you’re tempted to play with the air conditioner. But set the thermostat too high, and the air conditioner won’t dehumidify your air effectively; set it too low, and you create cold surfaces where water vapor can condense. To prevent moisture problems and maximize energy efficiency, set the thermostat at 78 degrees F.
3. Shut Windows and Doors When AC is On. When you open windows and doors, you let air conditioning escape, waste money, and invite humid air into your cooler home. This causes condensation, which mold loves. So keep doors and windows shut when the AC is humming. Also, maintain your home at around 80 degrees when you’re on vacation or at work. Too often, we bump the thermostat up to 85 degrees, or turn off the AC when we’re away. This raises temperature and humidity, which creates the ideal home for mold.
4. Properly Size Your AC Unit. Make sure your air-conditioning unit is properly sized for your house. If it’s too small, the unit will run constantly, elevating costs but not the temperature; too big, and the unit will constantly start and stop, which wastes energy, too. Install an HVAC unit that’s just right. For guidance, call an HVAC professional or consult Energy Star’s square footage/AC capacity chart.
5. Monitor Humidity. An indoor humidity monitor will help you keep track of moisture levels that, ideally, fall between 35% and 50% relative humidity; in very humid climates, at the height of summer, you may have to live with readings closer to 55%. But if you reach 60% relative humidity, it’s time to look for the source of the added moisture; above 70% relative humidity, certain species of mold can begin growing. Indoor humidity monitors start at less than $20; more sophisticated models that simultaneously and remotely track several rooms can climb to $200.
6. Evaluate Your AC

If you get a high humidity reading of 60% or more, make sure your air conditioner is doing its job.

• Is it set to the proper temperature?
• Is it cycling on and off periodically?
• Does it blow cold air when it reaches the set point?
• Are the coils clean?

Inspect the condensate drain pipe (the narrow white pipe sticking out the side) to make sure it’s dripping regularly. If it isn’t, the pipe is blocked and water may be accumulating inside the unit — or on your floor. If you suspect a problem, call your HVAC professional. To prevent blockage and mold buildup, pour a cup of bleach mixed with water down the drain annually.