Understanding how mold develops, where to locate water damage, and what to do about it will help you prevent mold after water damage.
Why Mold Develops After Water Damage
No single factor creates mold. A combination of water, food, temperature, and time create the conditions that allow mold to grow after water damage.
Water: Water, either in liquid or airborne form, is necessary to create mold. Humidity levels of 80-percent or more especially will trigger mold growth. Food: What is sometimes termed “food” for mold growth is some type of organic product such as the wood content in drywall paper, glues, or simply dust, dirt, and other loose debris. Temperature: Temperatures of 80°F or higher are usually necessary to grow mold. Time: Mold does not occur immediately after the water damage. Under certain conditions, it will take a few weeks for the mold to develop. Oxygen: Oxygen is required to grow mold. Yet to prevent mold growth, much ventilation will be required to dry out the area.
Where to Locate Hidden Water Damage
Water damage is often evident when you see standing water, watermarks on a wall, or blistered paint. Other times, water creates damage you may not know about because it is more hidden.
Behind wallpaper Back of drywall Inside walls Under carpet Under carpet padding On insulation Between siding, housewrap, and house sheathing Framing studs Wall floor plates Door trim
Tips for Mold Prevention After Water Damage
Work Quickly
Timing is important for preventing mold growth after water damage. The faster you work, the less chance of mold growth. Studies show that, under optimum conditions for mold growth, mold will develop around 5 weeks after the flooding. Most mold remediation experts recommend drying out the area far earlier than that.
Remove Water
For large water events, start with the wet/dry shop vacuum that you may already own. As soon as possible, rent an industrial-grade wet/dry vacuum from your local rental yard or home center. These models have large tanks, up to 55 gallons. Some models have pump discharges.
Use Fans to Dry the Area
To avoid losing time, begin with any available fans you may have on hand. Box fans push air at a rate of only 1,820 CFM (cubic feet per minute). Rentable 36-inch industrial fans are capable of moving over five times as much air.
Use Dehumidifiers for Continued Drying
Rent industrial-quality dehumidifiers to dry out the air faster. Even inexpensive rental dehumidifiers can pull 18 to 20 gallons of water from the air per day, plus they have automatic pump-out features that help you avoid constantly emptying the water tank. Fairly robust consumer-grade dehumidifiers can only absorb around 5 gallons of water per day and have small tanks (under 1 gallon).
Start With the Worst Contaminants
Differentiate between clear water, gray water, and black water damage. Clear water is visibly clean, though still will contain microbes. Gray water is dirtier and comes from sinks, showers, and washing machines. Black water, the dirtiest, is contaminated with human or animal waste. If possible, clean up the black water damage first before proceeding to the gray and clear water damage.
Dispose
Dispose of as much unwanted waterlogged material as possible. Disposal is the only way to ensure that the material will not develop mold weeks later. Remaining materials that have even a trace amount of moisture can possibly grow mold.
Stay Aware
Once done, keep aware of red flags that may mean that the water hasn’t been eliminated or that mold is growing. A musty smell in the area likely means that mold is developing. Check areas by touch or with a moisture meter to see if they are completely dry. Two-by-fours, carpeting, or drywall may look dry but will feel wet when you touch or test them.
How to Prevent Mold After Water Damage
Tips for Preventing Mold Before Water Damage
Eliminate the conditions that encourage mold growth or which make it more difficult to properly clean up the water damage.
Clean carpeting: Dirt in and under carpeting contributes to mold just as much as water. Regularly vacuum the carpeting and occasionally have the carpet professionally cleaned.Install mold-resistant drywall: After you’ve torn out the water-logged drywall, replace it with mold-resistant drywall that has a treated core and a fiberglass mat facing, not paper.Install a wall vapor barrier: After removing the old insulation and drywall, use a polyethylene vapor barrier for the new insulation.Install mold-resistant foam insulation: Sprayed foam and foam board insulation products are mold-resistant. Foam boards work well for framing against concrete or block basement walls.Keep fiberglass clean: Fiberglass insulation is actually a poor material for encouraging mold growth since it’s made of spun glass fibers and plastic. Dirt, debris, and water do encourage mold growth, though. So, if you decide to use fiberglass insulation, keep it clean and dry.Use dehumidifiers: Use consumer-grade dehumidifiers on a regular basis to keep the humidity level down to 50-percent or lower.
