9 Tips for Preventing Mold After Water Damage

A bold strategy to get rid of the most dreaded houseguest

A modern bathroom with minimalistic shower
Photo: photographee.eu / Adobe Stock
A modern bathroom with minimalistic shower
Photo: photographee.eu / Adobe Stock
C.E. Larusso
Written by C.E. Larusso
Contributing Writer
Updated October 24, 2023
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Water is a soothing element, which is why the sound of ocean waves is so relaxing. Too much water in your home, however, can be a harbinger of mold—and stress. After a pipe bursts or a natural disaster like a hurricane occurs, a buildup of water in your home can lead to mold and mildew. If you’ve experienced water damage, run (don’t walk—mold grows quickly!) to read our tips before mold makes itself comfortable in your home.

Before trying to tackle mold removal on your own, keep DIY mold removal dangers in mind. Improper removal of mold can lead to thousands of dollars in repairs and mold remediation down the line, so you may be better off leaving this job to the pros.

How Mold Grows After Water Exposure

As we’ve already mentioned (but it bears repeating!) the biggest risk factor for mold is moisture. So if you’re dealing with a leak or water damage of any kind, not only should you work to stop that issue, you should also be taking quick precautions to avoid mold growth. 

Mold and mildew can develop within 24 to 48 hours after water exposure, so act immediately to clean things up and get your house back to its dry state. The sooner you spring into action, the more you can contain potential mold growth and avoid the associated health risks. 

In the hours and days that follow water leaks, look out for discoloration, fuzzy growths and musty smells—all icky tell-tale signs of mold growth.

6 Mold Prevention Steps to Take Following a Leak

Before you go on mold patrol, take the following steps to stop it from happening in the first place.

1. Stop the Leak

Find the source of the leak flooding your home or other potential causes of unwanted water. Remember, water conducts electricity and floodwaters may contain bacteria, so coming into contact with it could be dangerous. When a pipe has burst, turn off the main valve if it is safe to do so, and call a local emergency plumber.

2. Clear Out Standing Water

Rent a wet-dry vacuum to remove standing water in your home if the area is smaller than 10 square feet and there is less than an inch of water. Protect yourself with the right gear before coming into contact with contaminated water. Thrown on some safety glasses, gloves, boots, long sleeves, long pants, and a mask (like an N-95 respirator). If the standing water consumes an area larger than 10 square feet or there’s more than an inch of water, call a water damage restoration company in your area for help.

Check outside your home as well for groundwater or water collecting against your foundation. Water can seep into your home and lead to mold growth. 

3. Remove Damp Items

Remove, dry out, and clean damp items, and store them outside until your insurance can review the damage. Otherwise, these items can stay moist and possibly harbor mold. Look for porous items that may have gotten wet, including carpeting, rugs, wallpaper, drywall, ceiling tiles, insulation, clothing, paper, wood (including furniture), and food. 

Some building materials like drywall, ceiling tiles, wallpaper, insulation, and carpeting will have to be replaced, or you run the risk of mold growing in and behind them and spreading. In addition, removing wet items will help reduce the overall humidity in your home, which can cause mold and mildew. The cost to rip up carpet and install laminate flooring averages between $1,590 and $4,690.

4. Clean All Surfaces

If you know how to check for mold and already notice some mold growing, stop it dead in its tracks. If you’re dealing with a smaller area, such as 10 square feet or less, you can choose to clean it yourself. 

Sanitize hard surfaces, such as baseboards and walls, with a cleaning solution made of 1.5 cups of fresh chlorine bleach to one gallon of water. Wear protective gear—such as a face mask and rubber gloves—while cleaning with this solution.

  • Spray a solution of 10% fresh bleach to 90 percent water on any visible mold. 

  • Let the solution sit for 10 minutes. 

  • Rinse and allow the area to dry. 

For soft surfaces, try an antimicrobial cleaner or undiluted white vinegar.

5. Give Your House a Chance to Dry Out

While you’re waiting for the right home flooding repair pro to show, air out your home. Open all windows and doors, set up several fans (aimed towards windows and doorways) to send humid air out, and run dehumidifiers for at least a few days. Look for a humidifier with a larger tank that will collect 60 or more pints of water per day, so you won’t have to empty it as often. Be on the lookout for musty smells that are indicative of mold. 

Check the Size of Your Bath Fan

Mold loves the moist, humid environment of bathrooms, and the right fan will help you control the humidity levels. Your bathroom fan should clear the room of moisture after five to 10 minutes. If it takes longer than this, you probably need a bigger fan. 

CFM, or cubic feet per minute, measures how much air a fan moves. To find the appropriate CFM for your bathroom, multiply the square footage of the room by 1.1. If this number is larger than the CFM listed on your fan (usually labeled under the grille), replace it with a larger model.

6. Hire a Professional

An empty room in a new house
Photo: pics721 / Adobe Stock

Mold can hide in air ducts, behind walls, and underneath carpeting. If you think your HVAC system has been affected, don’t turn it on. Call a pro to inspect and clean your unit. If water damage or a mold problem feels out of control, it’s best to hire a certified mold removal provider near you to evaluate the situation and quickly get things back to a normal, drier state.

Additional Mold Prevention

If you want to kick your mold prevention up a notch, take these additional precautions. 

1. Install Humidity Sensors

As a preventative measure, install humidity sensors in your home that will alert you if humidity levels are too high or too low. You can also purchase bath fans with humidity sensors; these smart fans will turn on when the moisture is high and turn off when it drops to normal levels, so you don’t have to worry about remembering to leave the fan on each time you take a shower.

2. Use Paint with Mildewcide

In rooms with high moisture and humidity, such as the kitchen and the bathroom, opt to use paint that contains mildewcide on your walls. Many paint manufacturers already include mildewcide in their formulas, but check to be sure.

3. Prevent Future Plumbing Crises

To prevent future mishaps, shut off the main water valve (and drain your pipes if you expect temperatures to drop below freezing) when you go on vacation. You can also install “no-burst” hoses on your washing machine, faucets, and toilets.

Frequently Asked Questions

There are a few signs that might indicate that mold is living behind your drywall. You might notice water stains on your walls or the ceiling, or see the wallpaper begin to peel. Wearing a mask, you could prod at any suspicious areas with a screwdriver; if the wall feels weak or soft, it’s likely there is water damage and possibly mold.

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Learn more about our contributor
C.E. Larusso
Written by C.E. Larusso
Contributing Writer
A professional content writer, C.E. has written about all things home, family, and wellness for a variety of publications, including HomeLight, Noodle, and Mimi. A third-generation Los Angeleno, she is always looking for ways to make the most of the sun, whether it be building an urban garden or decorating with the help of some low-maintenance, air-purifying plants.
A professional content writer, C.E. has written about all things home, family, and wellness for a variety of publications, including HomeLight, Noodle, and Mimi. A third-generation Los Angeleno, she is always looking for ways to make the most of the sun, whether it be building an urban garden or decorating with the help of some low-maintenance, air-purifying plants.
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