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Black Mold in Window: How to Get Rid of Them? (Answered)

Black mold in the window is one of the ugly and unhygienic things in your window. Black mold in the window makes the window look unattractive. Even black mold might come back again and again after cleaning them. Moreover, black mold spreads faster.

So, you might be confused about why the black mold in the window. Moreover, you might want to know how you can get rid of them.

You must know about the removal process of black mold. Besides, applying prevention methods is also essential. Otherwise, you can’t get rid of black mold in the window.

What causes black mold in the window sill or frame?

Moisture leakage and condensation are the two common causes of black mold in the window sill or frame. Poor ventilation and leakage from pipes also enhance the growth of black mold. Moreover, dirt and dust, soil particle, etc., can also cause black mold growth on window sill or frame.

However, different reasons might be responsible for mold build-up in window sill or frame. If you want to know the solutions, you must know the reasons in detail. So, let’s see what causes black mold in the window sill or frame.

Water leakage:

Windows will go through a lot of water and moisture. Because windows are placed on the wall. So, water and moisture problem is common for windows. Water leakage and moisture can be responsible for black mold build-up in the window.

When the window remains wet from the water leakage, it will be suitable for black mold build-up. So, water leakage can be a big problem.


Vapor condensation in the window sill or frame can cause black mold. Generally, the temperature inside and outside has differences. For the temperature difference, the window faces a condensation problem.

Condensation will also keep the window damp for a long time. So, the window will be a perfect place to grow mold.

Dirt and dust:

You might know that a window sill or frame accumulates more dust and dirt than other surfaces. Because the window faces the outside elements more. This dirt and dust help black mold to grow in the window more.

Poor ventilation:

Now you might say that window has the most ventilation. But sometimes, the windows are closed for a long time. 

For this reason, the windows are congested, and molds find a suitable place to grow. Because mold likes to grow in congested, humid, and poorly ventilated areas.

​​What does black mold on the window look like?

Now that you know different reasons for black mold build-up, you might want to know about their appearance. Because different places might have different appearances of the black mold. Let’s see what black mold on these windows looks like.

Window glass:

Black mold can grow on the window glasses also. On the glasses, you will see the black-green appearance of the black mold. The molds are generally located on the edges first.

So, you will see black spots on the edges of the window glass. Moreover, the glass will look dirty. The dark spots will look like round-shaped patches.

Wood window sill:

Black mold on the wood window sill will look like black and ash-colored patches on the edges of the sill. 

You will see mold on the sill and recognize it easier for its black color. You might think that the dark spots are a spider’s net. But actually, the black spots are black mold.

Wood or metal window frame:

Black mold on wood or metal window frame is dark black or gray. Moreover, the appearance of the mold on the wood or metal window frame will be round splotches with a speckled texture.

How to get rid of black mold in the window?

Black mold in the window makes the appearance of the window ugly. Moreover, it can damage the window eventually. You can use vinegar, baking soda and other cleaning element to get rid of them. Even controlling environment can also help to get rid of them.

If you want to get rid of black mold in the window, you have to follow some tips. Let’s see how you can eliminate black mold in the window.


First, you have to lean the window with different effective elements to remove black mold from the window. To do this, you have to vacuum clean the window. Then you have to wipe away the window with a damp cloth.

Now, you can mix ½ cup of bleach in one gallon of water. Mix the element with water very well. Then you can spray the mixture on the window. You can use the solution on the window glass, sill, or frame of the window.

Then you have to rub the surfaces with a brush. Rub the surface until the surface is clean. Then you have to rinse the window with clean water.

After that, you have to dry the window properly. Drying after clearing is very important. Because if you can’t dry the window after washing, mold can come back again and again.

Vinegar and baking soda:

You can also use vinegar and baking soda to lean the window from black mold. Generally, you have to make a mixture of vinegar and baking soda. The ratio of the mixture of baking soda and vinegar can be 2:1.

After making the cleaning agent, you have to spray this solution on the black mold in the window. If the sill or frame has black mold, you have to spray this solution there, also.

Then you have to use a brush to scrub the surfaces. Then you can use clean water in the window. Most importantly, dry the window very well before using it again.

Other cleaning agents:

Other cleaning agents are also available to remove black mold. Generally, commercial mold removers are very effective and fast. So, you can also use these commercial black mold removers on the window.

Controlling the environment:

You can also get rid of black mold in the window by controlling the environment near the window. 

For example, you Kan reduce the moisture leakage and condensation problem from the window. Moreover, you have to clean the sill and frame to remove black mold from there.

If you only lean the glasses and don’t clean the frame or sill, the growth of black mold will return from these places.

Is black mold in the window dangerous?

Black mold can be dangerous sometimes. Especially it can be severe for people who have allergies to mold. When the black mold is in the window for a long time, it can cause different medical issues.

For example, the black mold in the window can cause irritation problems if you go closer to the window. Moreover, it can cause allergic reactions in some people. So, the window black mold can be severe for them.

Besides, if you inhale the black mold in the window, it can cause breathing problems. Even some other medical issues can arise from inhaling the black mold. So, you must get rid of the black mold in the window for your and your family’s health.

How to prevent black mold in the window from coming back?

Now that you know the different reasons for black mold and the removal technique, you might want to prevent them. 

If you prevent the black mold from growing, the effort to clean the window will be less. So, let’s see how to prevent the window’s black mold from returning.

Fix the water leakage:

To prevent black mold growth in the window, you have to fix the water leakage problem. The water might come from different sources. So, you have to control the sources so that the window is not wet for a long time.

Reduce condensation:

When the temperature outside and inside the window has a big difference, condensation might occur. So, you can try to reduce condensation with a sound heating system. The heating system will keep the window dry and heated.

Keep clean from dust and dirt:

You might know dust and dirt help the black mold to grow more. So, you can always try to keep the window clean from dust and dirt. You can clean the window every week properly. 

Moreover, you must also clean the sill or frame because these spaces also grow black mold.

You might think that you will clean the windows when they are dirty with mold. But the mold will come back again and again if you don’t prevent it earlier. So, the prevention will be more efficient than removing the mold later.

Provide ventilation:

You might know that poor ventilation also helps to grow mold in the windows. So, you can try to provide enough ventilation to the windows. 

Don’t keep the windows open for a long time. Open the windows sometimes so that the window can get enough air and sunlight.

Prevent other leakages:

You must prevent other leakages on the window. For example, leakage from the pipe can be dangerous for the window. It will build up black mold. Moreover, it will damage the window gradually. 

So, you must prevent other leakages from the window to prevent the build-up of black mold on the window.

Final Thoughts

Black mold in the window is pretty common. Moisture, condensation, poor ventilation, dirt, dust, soil particle, etc., can be responsible for the black mold build-up in the window. You can also remove the black mold from the window and prevent them so that they can’t come back again.