How to Get Rid of Black Mold On Windows. Removal and Prevention

Black mold is a concerning sight in any home. Often found on windowsills and frames, not only is it ugly, but it can actually cause structural damage over time. More critically, various types of black mold can pose serious health risks, too. Taking action at the first signs of mold and knowing how to get rid of black mold can save both your health – and your home – from more severe consequences.

What is Black Mold?

Black mold, often referred to scientifically as Stachybotrys chartarum, thrives on organic materials like wood, wallpaper, and drywall. It doesn't grow on glass directly but adheres to the dust and moisture accumulated on it. Mold is characterized by its dark appearance and can give off a musty odor which gets in the air and poses health risks.

Identifying and Misidentifying Mold from Black Mold

Identifying mold accurately in your home is crucial for effective treatment and prevention. Mold often appears as a patch of discoloration that can range from black and green to white and orange, depending on the species. It typically has a fuzzy or slimy texture and might give off a musty, earthy odor. However, not all discolored patches or musty smells are due to mold, and misidentification can lead to the wrong fixes.

Characteristics of Mold:

• Texture: Mold has a distinct texture that can be fluffy, fuzzy, or slimy. Unlike dirt or soot, which are dry and powdery, mold tends to be sticky or wet to the touch.
• Color: Mold comes in various colors. Black mold (Stachybotrys chartarum) is dark black or sometimes greenish-black. However, mold can also appear white, green, red, blue, or even pink.
• Smell: Mold typically produces a strong, musty smell — a strong indication of mold even if you can’t see it.

Common Types of Mold Misidentification:

• Dirt or Dust Accumulation: Sometimes, what appears to be mold is simply an accumulation of dirt or dust. These are generally and overall brown or black color and lack the texture or distinct smell of mold.
• Efflorescence: This is a white, powdery substance that can appear on concrete, stone, and brick when water evaporates off the surface. Unlike mold, efflorescence is made of small crystals and will dissolve in water.
• Soap Scum: In bathrooms and kitchens, soap residue mixed with hard water (water that has a higher amount of minerals) can lead to deposits that may look moldy but are easily wiped away without the need for mold-specific cleaners.
• Staining from Rust or Water Damage: Water leaks can cause rust and other types of staining that might be mistaken for mold. These stains are usually found beneath a consistent source of water and do not grow or change appearance over time.

Tips for Accurate Identification:

• Moisture Check: Mold grows in moist environments. If the suspicious area is perpetually wet, mold is likely the culprit.
• Bleach Test: Dab a small amount of bleach on the area. If it lightens after one to two minutes, it's likely mold.
• Professional Testing: If you’re not sure, it's best to contact a professional who can test the material and confirm whether it's mold or another substance.

Actions Based on Identification:

• If Mold is Confirmed: Follow appropriate cleaning guidelines or hire a professional for more extensive infestations.
• If Not Mold: Clean the area with appropriate household cleaners based on the substance identified.

Knowing the difference helps ensure that you are treating actual mold issues in your home and not mistakenly applying mold-cleaning techniques to harmless or different substances. This not only saves effort and resources but also helps maintain the integrity and cleanliness of your home.

Common Causes of Black Mold on Windows

Mold growth on window sills typically stems from persistent moisture, which can arise from several sources:

• Condensation: Often occurs when warm indoor air meets the colder surface of the window glass. This is most frequently seen on single-pane windows, or on dual-pane windows that have a broken internal seal that allows the insulating gas between the panes to leak out.
• Leaking Windows, Damaged Window Frames/Window Seals: Cracks in the frame or glass, or poor seals/insulation can allow moisture to seep in and create a mold-friendly environment.
• High Humidity Areas: Kitchen and bathroom windows are prone to mold due to steam from cooking and bathing.
• Flooding or Heavy Storms: When water goes where it shouldn’t – like seeping in around old window seals outside your house – mold usually follows close behind. Act fast whenever you suspect a plumbing issue has caused water to leak into your walls

Health Risks Associated with Black Mold

Exposure to black mold can lead to various health issues, especially for individuals with respiratory conditions or allergies. Common symptoms include:

• Respiratory problems, such as asthma attacks or difficulty breathing
• Allergic reactions, with cold-like symptoms such as reactions like sneezing, headaches, red eyes, and skin rash
• Neurological symptoms such as headaches, dizziness, anxiety and depression

Mold Prevention Tips

1. When you go out of town, remember to keep the air on. A feeling of mustiness is often the early signs of a mold outbreak, and the dry air from the HVAC system can help prevent mold growth.
2. Open the windows to bring in fresh air. This can help reduce mold spores and humidity in your home.
3. Limit the amount of plants you keep on your window sill. Plants can create micro-biomes in areas with higher humidity (like a kitchen), which encourages mold growth.
4. Run the fans in the bathroom when you shower. This will help remove moisture and vent it outside.
5. Use your kitchen exhaust fan while you cook. Not only will this remove strong odors, but helps disperse the moisture so it doesn’t stay concentrated in one spot.
6. During humid summer months, use dehumidifiers and air conditioners to keep the air dry.
7. If you notice you have a drafty or leaky window, fix it right away.
8. Keep the air circulating in your home. A home with regularly circulating air is excellent for your health, and will prevent mold from returning.
9. In winter, ensure your home is well insulated to prevent warm indoor air from condensing on the colder surfaces of windows.

Economic Impact of Mold

Ignoring mold can lead to significant financial strain. Property values can decrease due to the damages caused by mold. Black mold on your windows is a living thing that grows by digesting the organic materials around it. If left untreated, it will eventually destroy whatever it lands on, and continue to expand outward. The frames of your windows will deteriorate, then it may spread into your drywall and into the structural components of your home. If the mold spores become airborne, they can start to grow and hide out in unexpected places. It’s not unusual to find mold in fabric, couches, mattresses, or lampshades. If you have mold between your double-paned windows, the seal is broken on your window. With a broken seal, that window is no longer energy efficient. You are spending extra money every month on heating and cooling. Health care costs may also rise due to respiratory issues and allergies exacerbated by mold exposure.

DIY vs. Professional Remediation

While small mold problems can often be managed at home, larger infestations require professional attention. Assess the size and depth of the mold:

• DIY: Safe for areas less than 10 square feet.
• Professional: Necessary for areas larger or if mold is inside walls or HVAC systems. Professionals use advanced tools and techniques to ensure mold is completely removed.

How to Clean Black Mold

If mold is confined to a small area, you can attempt to clean it yourself with the following steps:

• Protect Yourself: Wear protective gear such as gloves, goggles, and an N-95 mask.
• Prepare Your Cleaning Solution. There are a few different options for cleaning solutions. White distilled vinegar will kill about 80% of mold species on contact. If you’d like to increase the potency of your solution, you can make a paste of vinegar and baking soda. Mix one part vinegar with two parts baking soda to create your paste. Depending on what type of surface you’re cleaning, you may be able to use bleach. If you’d like to use bleach, mix ¼ to ½ cup of bleach in a gallon of water to create your cleaning solution. You may also choose a commercial mold cleaning compound. Ask the folks at your local home store what they recommend. As always, don’t mix different commercial cleaning solutions together. You could create and release toxic gas into your home.
• For non-porous surfaces like glass and metal: Mix one part bleach with ten parts water.
  • For porous surfaces like wood: Use a solution of vinegar and water, as bleach can damage wood and isn't as effective
  • Clean Gently: Apply the solution using a spray bottle and gently wipe the mold away with a damp cloth. Avoid scrubbing to prevent mold spores from spreading.
• Dry Thoroughly: Ensure the area is completely dry after cleaning to prevent mold from returning.

Comparison Table of Cleaning Agents

Natural Alternatives for Mold Cleaning

• Tea Tree Oil Solution: Mix one teaspoon of tea tree oil per cup of water for a natural fungicide.
• Grapefruit Seed Extract: Similar to tea tree oil, use about ten drops per cup of water for effective mold removal.

FAQ Section

Q: Can I paint over mold to stop its growth?

A: No, painting over mold will not kill it. You must clean and remove the mold before painting.

Q: How often should I inspect my windows for mold?

A: Inspect seasonally, especially after wet or humid periods.

Q: What should I do if mold keeps returning after cleaning?

A: Persistent mold may indicate an unresolved moisture problem. It might be necessary to consult with professionals for a thorough assessment and remediation.