How to Prevent Black Mold From Growing on Your Windows

Finding black mold—or any kind of mold—growing on your windows can send anyone into a panic.  Homeowners know that when there’s mold growth, there’s typically an underlying problem causing its presence, and lingering moisture is the common culprit to this issue.

If you’ve spotted black mold on your windows, the time to act is now.  Ignoring mold of any kind can be hazardous to your health and to the structure of your home.  There are ways to both eliminate the black mold and prevent it.

black mold growing on a window

Black Mold Growth

Moisture is the main trigger for black mold growth.  Windows are vulnerable to moisture and therefore provide a good environment for mold to occur.  A few reasons behind window moisture in a home can include:

-Leaking pipes

-Windows located in areas of the home exposed to excess moisture like the kitchen or bathroom thanks to steam from appliances like the stove, shower, dishwasher, and running taps

-Poor airflow

-Deteriorating and damaged weather stripping around the windows

-Older windows with poor insulating features

Windows are especially vulnerable to black mold growth as they separate the inside from the outside, and the glass is the only barrier between two temperatures that can be drastically different.  Black mold loves damp conditions, and with condensation on a window to provide moisture, it doesn’t take much for black mold to grow and spread.

Removing Black Mold

Before you prevent the mold from returning, you’ll need to eliminate it first.  Because mold can be hazardous, you’ll need to wear gloves and preferably a respirator mask.  Use a vacuum to remove the mold from the windows.  The vacuum may not remove all of the mold, but that’s okay, you’ll use other products to completely get rid of it.  Be sure to clean your vacuum with a damp cloth and vinegar when you’re finished.

cleaning black mold off window

Next, you’ll need to damp the area with a disposable cloth and warm water.  This will prevent the spore from spreading.  Make sure to rinse the cloth between each wipe.  Now it’s time to use something a little stronger to rid the windows of mold.  Use warm water and detergent for the next wipe-down and for the final clean, bring out the bleach.  A mixture of warm water and bleach will kill the black mold spores for good.

Preventing Black Mold from Returning

Mold is living organism that feeds off of organic material to grow and spread.  To prevent black mold from taking hold on your windows, you’ll need to eliminate any “organic” source that allows the mold to thrive.  This means ultimately preventing condensation and moisture.  There are many ways to control the moisture in your home and you can apply more than one method at a time:

-Dehumidifiers: By taking the moisture out of the air, you’ll help prevent condensation from forming on your windows.  This method of prevention is most effective in rooms where there is more moisture present like in kitchen or bathrooms.  The steam from a shower, cooking, and appliances can fog up windows easily, but a dehumidifier will remove the water from the air.  Stopping condensation will prevent black mold growth.

-Exhaust fans:  Like dehumidifiers, exhaust fans remove moisture from the air.  Normally, bathrooms will have an exhaust fan because of the steam from a shower.  Kitchens will also have a fan to vent the fumes from a stove.  If you don’t have an exhaust fan in these areas of the home and you do see black mold on the windows, then this could be part of the problem.  Installing an exhaust fan will stop mold from taking hold on the windows.

-Weather stripping: Weather stripping is easily overlooked but when it deteriorates, you’ll immediately notice its absence. The caulking around the window is what aids in keeping out drafts, insects, and leaks.  It’s an extremely important part of the window’s anatomy and is often neglected by homeowners.  Old, damaged, or peeling weather stripping can be the reason why black mold is growing on the windows.  It’s an easy fix.  Purchase a tube of caulking appropriate for window sealing and apply a new layer around the window.

installing new weatherstripping

-Frequent cleaning: Preventing black mold can mean killing the spores or sanitizing the surface they take hold on with bleach.  Clean your windows frequently and you’ll stop black mold from forming altogether.  Use a mixture of bleach and warm water and thoroughly wipe down the window surfaces.

-Replace your windows:  Just because there is black mold growth on your windows doesn’t mean they need to be replaced; however, it could mean that your windows are old and not keeping out drafts or leaks.  If that is the case, then you do need to replace your windows.  While window replacements are a hefty investment, you’ll enjoy numerous benefits like regulated inside temperatures, lower energy costs, UV protection, and of course, no more black mold.

If you’re in the market for replacement windows in any of our markets across the Midwest, we hope that you’ll consider Feldco for your window replacement project.

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