Mold spores are everywhere. They float through the air and can settle on any surface. If that surface is damp and there’s a food source present, mold will grow.
The paper face on a damp sheet of drywall can be the perfect food source for a spore to dig into. Before long, the mold can multiply and spread across the entire wall and into the wall cavity, feeding on wood framing and flooring.
While it’s hard not to panic at the thought of a mold problem, you can handle most drywall mold scenarios on your own. According to the EPA, homeowners can remove mold on drywall under 10 square feet. Larger infestations might require a pro.
Steps for Removing Mold from Drywall
The following are some steps you can take to remove mold from drywall.
1. Stop the Source of Moisture
Before you start removing the mold from your drywall, you have to stop the source of moisture. Whether it’s a leaky window or pipe, a roofing issue, or water vapor weeping through a concrete floor, you have to fix the problem. Otherwise, mold will start growing almost immediately after you finish removing it.
2. Gather Your Drywall Mold Removal Equipment
When you remove mold, you’ll undoubtedly stir up spores and send them airborne. Wearing long sleeves and pants, as well as rubber gloves, a respirator mask, and a pair of safety glasses will help keep those spores from irritating you.
To help minimize the number of spores in the air, use a vacuum fitted with a HEPA filter to remove surface spores. It’s also a good idea to block the rest of the home off with plastic sheeting and run a negative-pressure HEPA air filtration system, which you can rent from most tool rental shops.
Other materials you’ll need:
- Medium-bristled cleaning brush
- Bucket or spray bottle
- Cleaning solution
- Box fan
- Cleaning wipes
- Wet/Dry Vacuum with HEPA filter and brush attachment
- Plastic sheeting and tape
- Primer, paint, and painting tools
3. Decision Time: Save or Scrap?
There are times when removing moldy drywall is safer, more effective, and less time consuming than cleaning it. If your drywall surface is soft to the touch, the moisture and the mold have taken their toll on its structural integrity. In this case, it’s better to remove the drywall, kill the mold on the framing underneath, allow it to dry, and start fresh.
4. Remove Surface Mold from the Drywall
If you decide to remove the mold from your drywall yourself, you’ll need to handle the surface spores first. Vacuum the entire surface with your HEPA-equipped shop vacuum. Use a brush attachment to ensure you’re breaking up the spores and removing as many as possible.
5. Kill the Mold
With most of the surface spores removed, you can start killing the mold. There are a few different products that you can use for this step:
- Concrobium Mold Control
- 2:1:1 ratio of baking soda, white vinegar, and water
- 3% hydrogen peroxide
Contrary to popular belief, bleach is not always effective for killing mold. It can kill the surface spores but won’t do much to attack the roots.
Spray or brush your solution on your drywall and allow it to sit for 10 minutes before brushing the surface in a circular motion with a medium-bristled brush.
If you’re using Concorbium, you want to wait until the surface is dry, then dampen the brush with a bit more Concorbium before you start brushing.
A quick cleaning with a household cleaning wipe should remove any residue that might remain after brushing.
6. Use a Fan to Dry the Wall
With the spores killed and residue removed, the next step is to let the wall dry. Set up a box fan and point it directly at the wall. Allow it to run for 24 hours to ensure that the wall dries completely.
7. Cover the Stains
After 24 hours, you might notice some discoloration on your drywall. Most of the time, this discoloration is simply an easily handled stain, not mold reforming. To be sure, you can use a mold-killing primer like this product from Zinsser. These primers create a fungicidal protective coating that can cover the stains while also killing any rogue spores.
Once the stains are no longer visible, you can paint over the surface with mold-resistant paint like these products from JH Wall Paints. These paints’ alkaline pH levels create an inhospitable environment for molds and bacteria.
8. Keep the Humidity Low
A humid environment can encourage mold regrowth in the future. Do your best to keep the space dry and mold-free by minimizing the humidity levels. Use a dehumidifier to keep the humidity between 30 and 50 percent to deter mold from growing in other areas.
Following these steps will help you remove mold from your drywall surfaces and discourage it from growing back.