How to Remove Mold from Walls for Good

Get rid of mold on your walls with these easy homemade sprays, then keep it from returning for good.

Just about every home develops mold at some point. Surprisingly, newer homes get it more often because their tighter seals around windows and doors make them retain more moisture than drafty old homes.

Signs of Mold Growth

Where You’ll Find It Growing

Mold on your basement or exterior walls occurs when water vapor in the air meets a cold surface and turns the vapor into a liquid. Bathrooms and laundry rooms develop mold because they’re typically very humid, and you’ll often find it growing on grout alongside mildew. Other humid areas include the walls and ceiling near humidifiers and any room with a hot tub or jacuzzi improperly installed indoors.

Mold also grows where there is (or has been) a water leak. Places like the cupboards under sinks are prone to mold. Once a pipe has leaked, there’s a good chance black mold will grow unnoticed within the wall until the problem requires expert removal and mold remediation by professionals.

Steps to Get Rid of Mold on Walls

These steps remove mold from painted or unpainted walls, drywall, cement, and ceilings using homemade natural mold remover recipes.

Step 1: Wear Protective Clothing

Mold can cause severe respiratory symptoms and skin irritation. Wear a filtered dust mask or respirator to avoid breathing in mold spores and goggles or eye protection to avoid irritation from the mold removers. To prevent skin reactions or cross-contamination, wear rubber gloves, long sleeves, and pants that you can launder in hot water, which will kill any spores they pick up. (Plan on immediately washing or discarding all of them.)

Step 2: Prepare the Area

First, clear the area of decorative items, curtains, and other objects. If you can’t remove something — like heavy furniture — cover it with plastic sheeting and use painter’s tape to secure the plastic. Then, protect the floor where you’ll be working by taping a piece of plastic to the floor and covering it with an old towel to catch drips.

Also, since mold spores can travel easily in the air, protect the rest of your home by shutting the door to the room where you’ll be working. If that’s not possible, or if the room is large, hang plastic sheeting to block off the area.

Step 3: Make Homemade Mold Remover Spray

Use the spray suggested for the type of surface you’re cleaning. Do not use these sprays simultaneously or immediately after each other since you should never combine their ingredients. Do not store unused portions — they’ll lose effectiveness after 2-3 hours. Keep the sprays away from children and pets, and use proper ventilation.

DIY Natural Mold Remover Spray

Combine 2 tablespoons of borax, 2 ounces of distilled white vinegar, and 16 ounces of hot water in a spray bottle. Do not use this at the same time as other mold removers. Follow the application directions for the type of surface you’re cleaning.

DIY Bleach-Based Mold Remover Spray

In a spray bottle, combine 2 ounces of chlorine bleach and 16 ounces of cool water. Do not use this at the same time as other mold-removers.

Step 4: Remove the Mold

The best remedy for mold depends on the type of surface you’re treating.

On finished, painted, or wallpapered walls and ceilings

Use the natural mold remover spray. Spray the area well, then immediately scrub it with a clean cloth or brush to remove the surface layer of mold. Then lightly respray the site, using only enough to dampen the spot — you don’t want it dripping. Wait 10 minutes and wipe it with a clean, fresh cloth. Let it dry overnight without rinsing — the remaining acetic acid from the vinegar will work overnight to finish killing mold you can’t see.

On tile, stone, concrete, and cement

Use the homemade bleach-based mold remover. Spray the bleach-based mold remover until the area is saturated but not dripping wet. Scrub it with a rag, scouring pad, or brush and wipe away the residue. Lightly respray the area, wait 15 minutes, and wipe the area with a fresh cloth dampened with water. Let the area dry overnight and inspect it the next day. Repeat if needed.

On Drywall

Unsealed or primed drywall or sheetrock is porous, so the mold you see has likely threaded its way below the surface. It’s best to remove and replace moldy drywall. If that’s not possible for whatever reason, use the homemade bleach-based mold remover until damp but not dripping, and let the affected area air-dry. Then, respray it, wipe away any residue with a fresh cloth, and reapply a final light round of spray. Let this dry overnight for the spray to continue killing mold as it dries.

On Textured or Popcorn Ceilings

When removing mold from popcorn ceilings, you must not saturate the area, or the texture may begin to peel away. Just lightly mist the homemade bleach-based mold remover, wait 24 hours for the site to completely dry, and repeat.

Step 5: Cover the Mold Stain

Killing the mold does not remove the discoloration. If the mold leaves a light stain, you’ll need to apply an oil-based primer, then use your preferred paint to cover the area once the primer is completely dry. Don’t skip the primer or use a latex version or the mold stain will still show.

Mold Prevention Tips

Since mold prefers a dark, humid environment, opening your windows daily to circulate fresh air is an easy way to discourage mold growth. If someone in your family has allergies, do this very early in the morning or late in the afternoon, when pollen counts are at their lowest. If opening your windows isn’t possible, at least open your curtains during daylight hours.

In Basements

• Condensation on your basement windows or walls will cause mold growth. If you find condensation, you need better insulation. Add weatherstripping around doors, caulk gaps around windows, and insulate walls if needed.

• Consider adding exhaust fans to basement bathrooms or laundry areas. These spots tend to have high humidity, which leads to mold growth. If you can’t add an exhaust fan, run a floor or stand fan at least once daily to circulate dry air.

• Switch to hard flooring. Although a carpet feels warmer underfoot in a basement, it also collects and traps moisture, leading to mold. Replacing carpet with a good barrier underlayment and hard flooring will help prevent mold in your basement. And you can always use throw rugs to keep your feet warm.

• Swap faux plants for real ones. Live plants help clean your home’s air, but their damp soil invites mold to grow in a stuffy basement. Silk or plastic plants don’t cause mold problems, especially if you keep your fake plants clean.

• Use a hygrometer to measure humidity and a dehumidifier to keep it in check. Together, devices help you maintain humidity around the ideal 30-50%. Make sure to empty the dehumidifier and clean its reservoir regularly, or it will become another source of mold in your basement.

In Bathrooms

• Use your bathroom’s exhaust fan. Run it while you’re showering and for 15 minutes after every shower or bath to remove excess humidity. In homes without exhaust fans, use a stand-alone fan to circulate air. For safety, opt for a battery-operated fan that you can clip to a towel rack or shelf.

• Squeegee or wipe the shower walls and door after every shower to reduce moisture. Or skip the squeegee and use this homemade daily shower cleaner spray that prevents mold and mildew. Then leave your shower doors open so that air can circulate. For shower curtains, shake them to dislodge water, then leave a gap to either side so air can circulate.

• Regularly inspect places prone to leaks. Watch for moisture at the base of toilets and beneath your sinks, and immediately fix any leaks you find.

In the Rest of Your Home

• Inspect appliance hoses. You should replace flexible hoses on washing machines and kitchen sink sprayers immediately if you see a leak or condensation and every five years, even if you don’t spot problems. If you don’t replace them on time, your homeowner’s or renter’s insurance won’t pay if they burst and cause water damage.

• Inspect your roof after storms. Look for loose shingles or other damage that could allow water to enter your attic or home.

• Keep your foundation clear. Don’t stack firewood or other items against your home’s foundation, or you’ll encourage water collection there that will seep into your basement walls.

• Fix cracks promptly. If you find gaps in your foundation or siding, fix them immediately to keep water out of your home.

• Clean your gutters in the Spring and Fall. Clogged gutters cause water to pool near your foundation, leading to water damage that causes mold.

Remember, mold won’t go away on its own. If you find signs of it growing on your walls, you need to take prompt action to remove it with these easy homemade mold-killing sprays. Then keep it from coming back by controlling your home’s humidity levels, promoting good air circulation, and cleaning routinely to remove mold spores.