How to Get Rid of Window Mold

Mold has been shown to have negative effects on one’s health. It can cause skin, respiratory and other health ailments. In addition, it can cost a lot of money to eradicate. Why risk your family’s health if you can take some steps to get rid of window mold? Read on to find out why you may have window mold and what you can do to get rid of it.

Why Mold Grows

Mold needs moisture and organic matter to grow. It can be both visible and invisible. When it’s invisible, a mold test or, even better, a company that specializes in mold is the best way to detect its presence in the air. However, homeowners can sometimes see black mold growing on windows in the spring time.

window mold

Since the winter weather often brings snow and rain, mold is provided the perfect environment to grow. The cold weather leads people to use their heat, and when the hot air hits the cooler window panes, condensation occurs. Similarly, a window that’s close to the stove or oven in a kitchen may be more prone to condensation when the air is hotter than a cold window.

Mold can grow on several different places on your windows. It can grow on the inside of the window, along the bottom since that’s where moisture tends to collect the most. It can also grow on the window sill, depending on what the window sill is made out of, such as wood or aluminum.

Mold can grow on the wood since wood is an organic matter.  If you have an aluminum sill, dust from even the cleanest house can accumulate and provide food for the mold to grow.

Keeping the area between the wooden sill and the glass pane clean of dirt will help. Scheduling a weekly or bi-weekly cleaning of this area will tremendously aide in reducing window mold.

Mold can grow not only on the sill but also on the glass itself. Like aluminum, glass isn’t an organic matter, but mold can grow from the dust. This is especially true if you have a double-paned glass window. Mold can easily grow between the two panes since air gets trapped, more easily leading to the formation of moisture.

How to Get Rid of Window Mold

First and foremost, you need to protect your skin and lungs when cleaning mold. Gloves are a necessity and should be high enough to cover your hands and wrists. Wear protective clothing that covers your arms. Depending on the severity of it, you may need to wear goggles to protect your eyes.

Keep in mind that each time you touch mold, thousands of spores go up into the air, contaminating the areas around them. Those spores then settle on whatever is around: furniture, the floors or you. Any item that comes in contact with the mold will need to be bleached or cleaned with whatever solution you have decided to use.

Laundry Detergent

On nonporous surfaces such as glass, you can use laundry detergent to scrub away the mold. Laundry detergent won’t kill the mold, but it’ll remove small amounts that have grown on windows.

You can mix 1 cup of detergent with 1 gallon of water and use a scrubbing brush or sponge that has a more heavy-duty scrubbing side to it. Be sure to wash the area with water afterwards.


For truly tough mold on your windows, you can use ammonia and water. However, you have to be careful since the fumes from ammonia can be toxic.

You can mix 2 cups of ammonia with 2 cups of water in a spray bottle.

Spray the area well, and then let it sit for at least 2 hours. Afterwards, wipe the area very well. Be sure to have children and pets leave the room while you are working with the ammonia, and fully aerate the house afterwards by turning on fans and opening up the windows.

Natural Methods

For a natural cleaning solution, you can opt for hydrogen peroxide, tea tree oil, baking soda or white vinegar. For hydrogen peroxide, you’ll want something that’s at least 3% to do the job. You can let the mix sit on the mold for at least 30 minutes before wiping it down.

The beauty of tea tree oil is that it’s a natural fungicide, and so leaving it on the area instead of wiping it away will help to keep spores from growing. For tea tree oil, you can mix 2 tablespoons with 2 cups of warm water.

Baking soda works great on porous and non-porous solutions. Two cups of water can be mixed with ¼ cup of baking soda.

White vinegar is another natural method and can be used in a concentrated form for serious mold or in a reduced concentration for less severe spots. For the heavier areas, simply spray concentrated white vinegar and let it dry so that the mold is destroyed. For lighter areas, mix half vinegar and half water.

Helpful Tips to Reduce Mold

Prevention can go a long way. To limit mold from growing, check weather stripping on windows to ensure that cold air isn’t coming in through the window and causing condensation to form when it hits the warmer inside air.

If you have severe window mold, consider using a thermal imager in order to allow you to see places where cold air may be leaking in, causing condensation. If you want to bring in professionals, a home energy audit company will actually use infrared and other measures to detect where it is that heat is escaping. This can reduce costs associated with future mold remediation, which can cost thousands of dollars.

Extreme Mold

In some more extreme cases, the mold may have grown to the point that it starts to spread to sheetrock. Unfortunately, at this point, it’s best to hire a company that knows how to remove mold that has grown to this extent.

A mold remediation company will have the safety equipment needed to handle sheetrock mold, as touching the mold poses greater health risks than just breathing in the spores that will be in the air.

Take some preventative measures by looking for leaks and condensation, and be sure to dust between the glass and pane regularly. Be on the look out for mold so that you can get rid of it using one of the cleaning methods outlined above. Vigilance will help to preserve your windows and will save you money and time.

If the problem can’t be fixed, it’s time to replace your windows. Chicago homeowners turn to Feldco for all of their window needs. We’ve been serving Chicago for over 40 years and have helped over 350,000 homeowners with their home improvement projects. Get a free quote now and get started on finding your dream windows today.

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