How to Remove Mold From Walls

Discovering mold on your walls can be an unpleasant surprise. Mold can develop quickly in areas with moisture, poor ventilation, or water leaks.

Why Mold Grows on Walls

Mold thrives in damp, dark environments, making walls—especially in bathrooms, basements, and areas with poor ventilation—prime locations for growth. While cleaning up mold is crucial, addressing the moisture issue is equally important to prevent future outbreaks.

Staying Safe During Mold Removal

You’ll need some supplies:

• Gloves: Protect your hands from both the mold and the cleaning agents.
• Goggles: Prevent spores from getting into your eyes.
• Mask or Respirator: Wear a mask (preferably N95 or a resperator) to avoid inhaling harmful spores.
• Ventilation: Ensure good airflow by opening windows, doors, or using fans. Cover nearby furniture and flooring with plastic sheeting to contain mold and cleaning solution.

Choosing the Right Mold Cleaning Solution

Different solutions work well for mold removal, depending on the wall type and your preference for natural or chemical options. Here’s a quick guide to help you choose:

• Vinegar: A natural and effective mold killer, vinegar can be used undiluted on most surfaces. Simply spray and let it sit.
• Baking Soda Paste: An abrasive that absorbs odors. Mix it with water to create a paste, apply it, and scrub lightly.
• Hydrogen Peroxide: Safe for many surfaces, hydrogen peroxide is an effective mold-killing alternative to bleach that can also help lighten stains.
• Bleach Solution: For tiles, grout, or other non-porous surfaces, mix one part bleach into three parts water. However, avoid using bleach on drywall, as it can damage it.
• Commercial Mold Cleaners: There are many effective commercial products available. Always follow the instructions on the label.

For those preferring all-natural solutions, tea tree oil, lemon juice, and borax are also antifungal options.

How to Remove Mold from Walls: Step-by-Step

1. Apply Your Cleaning Solution: Spray or wipe your chosen solution onto the moldy area. Make sure it covers the mold completely.
2. Let it Sit: Allow the solution to soak in for at least 10–15 minutes. This dwell time helps to kill mold spores effectively.
3. Scrub the Area: Use a soft brush or sponge to remove the mold. Avoid excessive scrubbing on painted surfaces to prevent damage to paint. Concrete or tile walls can handle more rigorous scrubbing if needed.
4. Rinse with Clean Water: After scrubbing, rinse with clean water to remove any residue from the cleaning solution. A damp cloth or sponge should work well here.
5. Dry Completely: Use fans, a dehumidifier, or open windows to thoroughly dry the area. Ensuring the wall is completely dry is essential to prevent mold from reappearing.

Special Considerations for Different Wall Types

• Painted Drywall: Be gentle to avoid damaging the paint. For stubborn stains, consider applying a stain-blocking primer and mold-resistant paint.
• Unpainted Drywall: If mold has deeply penetrated the surface, it’s usually best to cut out and replace the affected area to prevent further spread.
• Concrete Walls: Concrete can withstand more scrubbing and may benefit from a post-cleaning sealant to prevent future mold growth.
• Bathroom Walls: Because bathrooms are often humid, consider using mold-resistant paint or sealant after cleaning to help keep mold at bay.

How to Handle High Ceilings

Removing mold from high ceilings can be tricky and may require additional equipment. Use a sturdy extension ladder or scaffolding and ensure you have stable support. If mold is widespread on a high ceiling, it might be best to call professionals. When DIY-ing, use a pump sprayer with an extended wand to apply the cleaning solution and attach a brush to an extension pole for scrubbing.

Preventing Mold from Coming Back

Once you’ve cleaned the mold, take these preventive steps to keep it from returning:

• Control Humidity: Maintain humidity levels between 30-50% with a dehumidifier or by increasing ventilation. This is particularly helpful in moisture-prone areas like bathrooms, kitchens, and basements.
• Fix Leaks Promptly: Address any plumbing, roof, or window leaks immediately to reduce the chance of mold growth.
• Use Mold-Resistant Materials: Use mold-resistant drywall or paint, especially in areas where moisture is recurring.
• Routine Cleaning: Regularly clean and check areas prone to moisture and mold, such as bathrooms, kitchens, and basements.

When to Call a Professional

In some cases, mold removal is best left to the experts:

• Large Infestations: If mold covers over 10 square feet, it may require professional equipment and expertise.
• Hidden Mold: Mold behind walls or in HVAC systems is hard to access and may require specialized tools.
• Health Concerns: If you or someone in the household has allergies, asthma, or a weakened immune system, professional removal can help reduce exposure to mold spores.

Final Thoughts

Removing mold from walls can often be a manageable DIY task, especially for smaller areas. You can keep your walls clean and mold-free with the right cleaning solution, protective gear, and preventive measures. Remember, addressing the root cause of moisture is key to preventing mold from returning.