How to Remove Drywall Mold: DIY Steps

Mold in your home or business can lead to extensive property damage, compromise indoor air quality, and pose serious health risks over time. Drywall, in particular, is highly susceptible to mold because of its porous nature. Once it becomes damp—whether due to high humidity, leaks, or flooding—mold can grow quickly behind or on the surface of the wall.

If you’ve spotted mold on your drywall, it’s important to act fast. In this guide, we’ll walk you through:

• How to identify mold on drywall
• Types of mold commonly found in homes
• When to clean vs. when to replace moldy drywall
• Step-by-step instructions to safely remove mold from painted drywall
• Mold cleaning solution options (natural and chemical)
• When to call a professional mold remediation specialist

How to Identify Mold on Drywall

Mold on drywall often appears as stains or patches, typically found in areas with high moisture levels. It thrives in poorly ventilated spaces such as bathrooms, basements, kitchens, and laundry rooms. Mold can also develop after water damage, as drywall absorbs standing water, creating the perfect environment for growth.

While visible dark patches on walls can help you identify mold, it’s not always that easy. In many cases, mold may grow hidden inside the walls. Here are some common signs that there could be mold in your drywall:

1. Stains and discoloration: If you see brown or yellow stains on your walls, you may have mold behind them. If these spots are damp, this is a sign of water damage which means mold is already there or is likely to appear.
2. Deterioration of paint or wallpaper: If your paint or wallpaper is peeling, cracking, or bubbling, this may be caused by mold growth. Damage such as warping, bowing, or bulging is also a sign of water damage which can lead to mold growth.
3. Odors: Detecting mold growth is often easy, as it typically comes with a distinct musty odor or a sense of stuffiness and stale air. These signs are strong indicators that mold may be present. Additionally, pay attention to any unusual smells coming from electrical outlets, as this could suggest mold hidden behind the walls.

What are the Different Types of Mold?

Mold on drywall often appears as black patches, but its appearance can vary depending on the type of mold. Here’s a breakdown of the most common types:

• Black mold: This type of mold often develops in homes that have experienced significant moisture damage. While it is not immediately harmful, prolonged exposure can lead to the production of mycotoxins, which may pose health risks if left untreated. Prompt remediation is essential to prevent potential harm.
• White mold: This type of mold commonly thrives in basements and is often mistaken for efflorescence, a crystalline salt deposit that forms in the presence of moisture. To determine if the substance is white mold, spray it with water. If it does not dissolve, it is likely mold.
• Blue mold: This type of mold has a bluish-green color and can appear within 24-48 hours after water damage has occurred. It does not require a lot of moisture, and it is usually found in drywall, wallpaper, ceilings, and insulation affected by water damage or in wet places such as bathrooms.
• Green mold: This type of mold is easily recognizable by its green color and is typically found in dark, damp areas, such as bathrooms.

Does Moldy Drywall Always Need to Be Replaced?

Not always—it depends on the severity and location of the mold.

You Can Clean the Mold If:

• It’s on a painted surface, not soaked through
• The affected area is small (less than 10 square feet)
• There’s no musty smell coming from inside the wall
• There’s no significant water damage

Replace the Drywall If:

• Mold has penetrated the drywall surface
• The drywall is soft, bulging, or crumbling
• You’ve had flooding or long-term leaks
• There’s mold growth on both sides of the drywall

Easy At-Home DIY Steps to Remove Mold from Drywall

Discovering mold on painted drywall may seem daunting, but fortunately, it’s relatively easy to clean. The paint acts as a protective barrier, preventing the mold from seeping into the drywall itself. All you need is a reliable cleaner and a bit of effort. However, before tackling the cleanup, it’s important to identify and resolve the source of moisture that caused the mold in the first place. Once the underlying issue is addressed, follow these steps to effectively remove mold from painted drywall:

Choose or Prepare a Cleaning Solution

If you’re planning to make your own cleaning solution, it’s essential to avoid mixing it with other cleaners unless you’ve thoroughly researched the potential risks. Some combinations can be hazardous. Alternatively, there are plenty of chemical and natural cleaning solutions readily available for purchase. Here are a few options to consider:

• Bleach and Water: Mix one part bleach with three parts water. This solution is strong and effective but should be used in a well-ventilated area.
• Vinegar and Water: Combine equal parts white vinegar and water. Vinegar is a natural disinfectant and safe for most surfaces.
• Baking Soda Solution: Mix one part baking soda with five parts water. This is a gentle, non-toxic option.
• Hydrogen Peroxide: Use 3% hydrogen peroxide directly from a spray bottle. It helps kill mold and disinfect the surface.
• Concrobium Mold Control: This store-bought product is designed specifically to eliminate mold and prevent it from coming back.

Important: Never mix cleaning chemicals like bleach and ammonia. This can create dangerous fumes.

Apply the Cleaning Solution and Scrub

Spray the affected area generously with your chosen cleaner. Let it sit for about 10 to 15 minutes so it can break down the mold. Then, gently scrub the surface using a sponge or brush. After scrubbing, wipe the area clean with a towel or cloth to remove any leftover mold and residue.

Dry the Area Completely

Use fans or a dehumidifier to dry the wall thoroughly. Mold thrives in moisture, so it’s important that the area is completely dry to prevent it from growing back.

Monitor for Any Signs of Return

Over the next few days or weeks, check the area to make sure the mold doesn’t return. If it does, or if the stain spreads or worsens, it could mean that mold is growing inside the drywall. In that case, you may need to cut out and replace the affected section.

How to Prevent Mold on Drywall

Once you’ve dealt with mold, the last thing you want is for it to return. The key to preventing mold is moisture control and a bit of regular upkeep. Here’s what you can do to keep it away for good:

• Keep Humidity Low: Mold thrives in humid air. Try to keep indoor humidity below 50%. Use a dehumidifier, especially in damp areas like basements or laundry rooms.
• Fix Leaks Immediately: Even a small leak behind the wall can feed mold. Check plumbing, roofs, windows, and foundation cracks regularly—and fix any issues right away.
• Improve Airflow: Good ventilation helps dry out moisture-prone areas. Open windows when weather allows, use fans, and run exhaust fans in bathrooms and kitchens.
• Use Mold-Resistant Materials: If you’re remodeling, use mold-resistant drywall and paint in high-humidity areas. Mold-resistant paint additives can also help protect existing walls.
• Dry Wet Areas Promptly: Don’t let water sit—on bathroom walls, in your basement, or under a leaky pipe. Wipe surfaces dry and clean up spills as soon as they happen.

Call a Mold Removal Expert When DIY Doesn’t Work

Mold on drywall is not just an aesthetic concern, it’s a serious issue that can lead to structural damage and health problems if left untreated. Recognizing the early signs of mold, understanding the different types, and knowing when to clean or replace affected drywall are key to maintaining a safe and healthy environment. Whether you’re tackling minor surface mold or addressing deeper infestations, taking swift, informed action is crucial. By identifying the source of moisture and using the right removal methods, you can effectively combat mold and protect your home or business for the long term.

If you find mold growth in your home, it is crucial to call a professional to remove it immediately. Mold remediation specialists can effectively contain and remove mold from any surface or materials, including drywall, using advanced remediation techniques. They can also repair the damage caused by mold and ensure that the home is restored to safe conditions.