Plaster typically goes moldy because trapped moisture combines with poor ventilation and cold surfaces, creating an ideal environment for fungus to thrive.
Remove mould from the walls with HG mould spray
You can see a clear result within 30 minutes. HG mould spray is self-acting and suitable for tiles, silicone grout and plaster. With 500 ml you can treat 2 to 3m2 wall surface and 6 to 8m2 tile grout. HG mould spray is also available as a mould remover foam spray.
Plaster walls are highly susceptible to mold growth when exposed to water. Drywall is typically treated to reduce the ability of mold to grow in the wall, but this doesn't stop it completely.
Signs of mould growth on plaster can be both visible and hidden. Common indicators include: Dark or discoloured patches (black, green, brown, or grey) on plaster walls or ceilings. A persistent musty or damp smell, especially in enclosed rooms.
Mold is significantly worse than mildew. While both are fungi that thrive in damp areas, mold penetrates deep into surfaces causing structural damage and releases harmful mycotoxins that trigger severe respiratory and neurological issues. Mildew remains entirely on the surface and is easy to clean.
Plaster is more resistant to mold than drywall because it lacks the paper facing that mold feeds on, but it is not mold-proof. While traditional plaster won't rot, it is highly porous and can grow mold if it stays wet for a long time, particularly on the wood lath behind it.
Mold toxicity (mold illness or mycotoxicosis) occurs when prolonged exposure to mold and its mycotoxins triggers systemic inflammatory and immune responses. The most common indicators range from persistent allergy-like symptoms (like sneezing, coughing, and red eyes) to neurological issues (like fatigue, headaches, and brain fog).
To kill mold permanently in walls, you must physically remove the existing mold with an EPA-registered fungicidal spray or white vinegar, fix the moisture source, and treat the wall with a Zinsser Mold Killing Primer to prevent regrowth.
Mold is typically worst from late spring through early fall. Because mold thrives on warmth, moisture, and oxygen, the combination of high humidity and rising temperatures creates the perfect breeding ground for spores to multiply rapidly both indoors and outdoors.
No, mold does not go away if it dries out. Drying out merely forces the active mold into a dormant, hibernation-like state. While it stops growing or spreading, the mold remains on the surface and continues to pose health risks, ready to reactivate the moment moisture returns.
White vinegar (undiluted) and specialized enzyme-based cleaners instantly kill and penetrate black mold. For most non-porous and porous surfaces, spraying full-strength distilled white vinegar and letting it sit works best. For tough cosmetic stains, hydrogen peroxide or EPA-registered mold removers work well.
The first signs of mold are usually a musty, earthy odor, unexplained allergy-like symptoms (sneezing, coughing, itchy eyes), and subtle visual indicators like water stains, peeling paint, or small discolored spots in damp areas like bathrooms or basements.
While you may see the mold, you may not be able to see the extent of the damage. Anytime mold is discovered on plaster, stucco, drywall, carpeting, or other flooring, it's important to have the mold professionally remediated for the health and safety of your home.
No house is 100% mold-free. Mold spores exist naturally in all indoor and outdoor environments, constantly floating in through doors, windows, and ventilation systems. While eliminating all spores is impossible, the goal is to prevent them from finding moisture and growing into active, spreading colonies.
Toxic mold on walls typically appears as clustered spots or irregular patches in shades of dark green, gray, or black. Textures range from slimy and wet to dry, powdery, or fuzzy, often accompanied by a strong musty, earthy odor.
How long mold takes to affect you depends entirely on your sensitivity, the amount of mold, and the length of exposure.
To test yourself for mold toxicity, consult a healthcare provider for medical evaluations like a urine mycotoxin test or a blood test. You can also use online symptom checkers or visual contrast sensitivity (VCS) tests, and assess your living space for mold.
Black mold is specifically known as Stachybotrys chartarum, which produces harmful mycotoxins and poses significant health risks like severe respiratory issues. Regular mold refers to common household molds that are less toxic but can still trigger allergies.
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.
People don't use traditional plaster for everyday construction anymore because it is significantly more expensive, highly time-consuming to install, and requires specialized, dying craftsmanship compared to modern drywall.
Plaster itself is inorganic and non-porous, making it highly resistant to mold. However, mold can and frequently does grow on painted plaster surfaces when dirt, organic debris, or condensation are present. Mold also often grows on the organic backing materials (like wood lath) hidden behind the plaster.
To kill mold permanently, you must combine targeted remediation with moisture control. No product works permanently if the source of moisture remains. The most effective approach includes using specific biocides, removing infested porous materials, and managing your home's humidity.
Mildew is essentially early-stage mold. It begins as a flat, powdery fungus on the surface of materials like shower walls, fabrics, or paper. If left untreated, the growth will deepen, mature into full-blown mold, and begin to infiltrate and damage the underlying surface.
For an instant kill, commercial bleach-based cleaners like Mold Armor Rapid Clean Remediation or CloroxPro Tilex destroy surface mildew and lift stains on contact without scrubbing. For a natural, non-toxic alternative, apply undiluted 3% hydrogen peroxide or white vinegar, letting it sit to kill the spores at their roots.