If the moldy area is small (less than 10 square feet) and only on the surface of painted drywall, you can often scrub and clean it. However, if the drywall is soft, crumbling, or the mold is on the back or inside the wall, you must remove it.
You can only treat mold without removing drywall if it is surface mold on the paint layer and the area is smaller than 10 square feet. If the drywall is soft, warped, or mold has penetrated the material, you must cut it out to prevent deeper structural damage.
Mould can pose a serious threat to your health, particularly if you have allergies or respiratory issues. In addition, it can cause damage to your drywall, which can weaken the structural integrity of your home.
Visible mold may take up to three weeks to show, but its spores can start growing in 48 hours. Once mold gets inside, it can cause drywall to bulge and crack. Mold growth poses risks beyond just damage.
For small outbreaks of surface mold on sealed drywall, scrub the area with a mild detergent or diluted vinegar solution using a stiff brush. Dry the area thoroughly. If the mold covers more than 10 square feet, keeps returning, or has gotten into unsealed drywall, contact a professional mold remediation service.
Mold toxicity (mycotoxin illness) happens when prolonged exposure to mold spores triggers chronic inflammation and immune system activation. Symptoms are often subtle and mimic other illnesses, but common red flags include persistent allergy-like reactions, chronic fatigue, unexplained brain fog, recurring headaches, and respiratory or digestive distress.
Yes. Mold behind drywall can negatively affect your health. Even though it is hidden, mold spores, toxic gases (MVOCs), and mycotoxins can seep out of the wall cavity through electrical outlets, cracks, and baseboards to degrade your indoor air quality.
To determine if mold is behind your drywall, look for surface signs like peeling paint, bubbling wallpaper, or warped drywall. Use your nose to check for a persistent musty smell. For definitive proof, use a moisture meter to find damp spots or drill a small hole to inspect the cavity.
Mold is generally at its worst from early spring through early fall (specifically July through October), peaking during the warmest and most humid months. Mold thrives in warm temperatures (60∘F to 80∘F) combined with relative humidity levels above 60%.
In A Nutshell: Misconceptions About Mold
Your home can be 100% mold-free: No, there are always mold spores in the air. Anyone can effectively remove mold: No, you need professional services for that.
Toxic black mold growth has a more potent and identifiable smell, like the smell of decay, wet soil, or rot. Visually, it may be greenish-black, grayish-black, slimy, or more furry than other forms of mold or mildew.
Bleach. If you don't have a specific mould spray, bleach can be used instead. Mix a solution of one part bleach and four parts water. Take a cloth and wipe this solution across the wall, scrubbing gently until all the mould has been removed.
Some drywall finishers add a small amount of dish soap (like Dawn) to drywall mud as a workability hack. They do this to act as a surfactant, which reduces the surface tension of the mud.
To kill mold on drywall, use 3% hydrogen peroxide, white vinegar, or specialized mold-control sprays. Bleach should be avoided on drywall; its high water content can feed the mold, and the chlorine only bleaches the surface stain without penetrating the porous material.
If the mold in your residence was caused by something sudden or accidental, such as a bursting pipe or some other covered incident on your policy, you may be protected. However, if the mold has been around for weeks or longer, your policy likely won't cover the expense.
Most mold-infested homes can be saved: Even houses with extensive mold contamination can typically be restored to safe, habitable conditions through professional remediation, though the process may be complex and costly depending on the severity of the infestation.
Additionally, spraying a solution of equal parts vinegar and water or a diluted hydrogen peroxide solution into the air can help to kill airborne mold spores.
Mold toxicity (or mycotoxin illness) occurs when you are exposed to mold spores that produce toxic byproducts. These symptoms can mimic other conditions and often range from mild respiratory irritation to severe neurological and immune responses.
The ideal temperature is between 77 and 86 degrees Fahrenheit. During the summer months, temperatures are often higher than normal inside the home. Make an effort to keep temperatures inside the home lower during the summer months. Setting the thermostat to the low 70s makes it more difficult for mold to grow.
Mold Removal Using Hydrogen Peroxide
Most home pharmacies contain hydrogen peroxide, an antiviral, antifungal, and antibacterial agent that removes mold. It's friendly on different surfaces, including hard floors, some wall surfaces, plumbing fixtures, household appliances, and countertops.
Within 24 to 48 hours of moisture entering your home, mold spores can begin to germinate. Within a week, you may have visible colonies spreading across drywall, wood, and insulation. The window to act is narrow, and what you do in those first hours determines whether you're dealing with a cleanup or a full remediation.
Mold hiding in walls typically has a distinct, damp, and musty odor, closely resembling the scent of a dark, closed-off basement, rotting wood, or wet socks. Because mold off-gasses chemical compounds as it grows, the smell can also present itself as earthy like soil, pungent like rotting hay, or even slightly stale and stale-sweet.
Before You Begin
Black mold on drywall is dangerous. It releases spores and mycotoxins that can cause severe respiratory issues, allergic reactions, and asthma flare-ups. Furthermore, because drywall is porous and made of cellulose, black mold feeds on it, degrading the structural integrity of your wall.
Yes, mold in one room can easily affect the whole house. Mold reproduces by releasing microscopic airborne spores that travel through air currents, HVAC systems, open doorways, and on clothing or pets. Once these spores land in another damp area, they can quickly begin to grow.