A flooded basement, moldy drywall and mildewed grout are no fun to deal with. Here are tips to help you prevent water damage and mold growth from happening in the first place, and tips for handling these situations if they do occur.
Tip 1: Control indoor moisture to prevent mold
The key to stopping mold and mildew is to control dampness. The worst infestations usually occur in damp crawlspaces, in attics and walls where water has leaked in from the outside, and in basements with poor foundation drainage. Stopping leaks, ensuring good ventilation in attics, keeping crawlspaces dry and routing water away from the foundation are the best defenses.
Tip 2: Make sure your bath fan is big enough
If the fans aren’t clearing out most of the moisture in your bathrooms after five to 10 minutes, your fans may not be moving enough air. Fans are certified by the volume (cfm, or cubic feet per minute) of air exhausted out of the room. To find the recommended fan capacity for your bathroom, multiply the bathroom square footage by 1.1 (assuming an 8-ft. ceiling; for a 9-ft. ceiling, multiply by 1.5). Check the cfm volume of your fan, usually marked on a label under the grille. Replace it with a larger model if it’s too small for the size of your bathroom.
Tip 3: Consider “smart” bathroom timers and humidity sensors
Bath fan timers are important because excess humidity can cause everything from window condensation and mildew to moisture and rot inside walls. Some new wall switch timers have dual controls for turning off both lights and fans after a preset time. For the ultimate in smart bath fan timers, buy a humidity-sensing fan designed to automatically turn on and off as moisture levels at the ceiling rise and fall.
Tip 4: Squeegee your shower every time you use it
After a bath or a shower, squeegee water off the shower walls. That eliminates at least three-fourths of the moisture that supports mold and mildew growth.
Tip 5: Clean visible mold immediately
Surface molds grow in just about any damp location, such as the grout lines of a ceramic tile shower. To get rid of mold, scrub with detergent and water and let the surface dry completely. Or use a solution of 10 percent bleach and 90 percent water (a stronger bleach solution will not give better results). Spray or brush on the solution, let it sit 10 minutes, then rinse it off and let dry. A nontoxic mold control product called Concrobium ($10 for 22 oz. at home centers) can be effective if used every few months.
Tip 6: Use paint with mildewcide in damp areas
Mildewcide in paint is usually effective for controlling surface mold in damp rooms like bathrooms and outside in shady areas. Many paints already have mildewcide in them. Check with your paint dealer to be sure.
Tip 7: Act quickly to stop a leak
A gushing plumbing leak can dump several gallons per minute into your home. You have to act fast to stop the stream. Shutting off the main water valve is an obvious move. But there may still be a few gallons of water held in pipes above the leak. Turn on the lowest faucet in the house, which will let the water harmlessly drain out of the faucet instead of through the leaking pipe.
Tip 8: Don’t delay cleanup
The longer things stay wet, the more likely you’ll have permanent damage. Delay can also lead to mold problems inside walls, which can cost thousands to eradicate. So before you run off to buy plumbing parts, clean up the mess. Pronto.
Tip 9: But don’t act rashly
Your first impulse will be to wade in and rescue your stuff. But that water might be dangerous, so put on your boots and take precautions. Any water in contact with electricity might be deadly. Stay out of the water until you, an electrician or your utility has turned off the power to your basement. Floodwaters may contain toxic chemicals and will almost certainly breed dangerous bacteria. Protect cuts and open sores from floodwaters and wear plastic gloves when handling your possessions.
Tip 10: Prevent the top causes of water damage
Don’t come home to a plumbing catastrophe. Shut off the main water valve when you leave for extended periods, use stainless steel “no-burst” hoses for washing machines, faucets and toilets, and use frost-proof outdoor faucets.
— The Editors of The Family Handyman