Although mold begins to grow within a day or two of taking root after a water or excessive moisture issue, it takes a bit longer for the mold colony to become big enough to be seen with the naked eye. If left unchecked, mold will become clearly visible within about two to four weeks.
Black mold begins to form and multiply within 12–24 hours when the conditions are right. If you've experienced water damage, be sure to take action immediately to dry and dehumidify the area to prevent spores from taking hold.
Black Mold Growth Rate
If you're wondering, “How long does it take for black mold to grow,” the answer is not long at all. The growth rate of black mold can be rapid, but it still depends on its environment. Generally, however, black mold can grow and form a colony within one or two days.
Many homeowners attempt to simply repair drywall that is infested with mold, but it should always be fully replaced. If you don't replace every part of your drywall that has experienced mold growth, you're only leaving your home vulnerable to much more damage in the future.
The growth of black mold can vary based on several factors, including the conditions of the environment and the availability of moisture and organic material. In general, under optimal conditions of high humidity and warmth, it can start to develop within 24 to 48 hours.
Visually, it may be greenish-black, grayish-black, slimy, or more furry than other forms of mold or mildew. If you try to clean it with a heavy-duty cleaner, you might find that it remains on the surface and doesn't completely wipe away.
The only way to prevent mold infestation in drywall following a water damage incident is to dry it within 48 hours after water intrusion. The 48-72 hour window is critical to prevent mold growth as it usually takes 24 to 48 hours for mold to germinate and grow.
Some of the signs of black mold in your house may be a musty smell, dark-colored tile grout, and warped drywall.
Cleaning mold off walls naturally can be achieved using household ingredients such as vinegar, hydrogen peroxide, or baking soda. Create a solution by mixing equal parts vinegar and water or hydrogen peroxide and water. Alternatively, make a paste using baking soda and water.
Homeowners insurance doesn't usually cover mold damage or removal unless it's the result of a covered peril. 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.
Aureobasidium
This yeast-type fungus can be mistaken for another more sinister and dangerous mold but is far less likely to make you sick. Aureobasidium can start as a slimy pink color, but it will turn brown or black and can look like black mold.
If you're allergic to black mold, you may have symptoms immediately after spores come in contact with your body. If you're not allergic to black mold, you may not have any symptoms, or your symptoms may not appear for a long time.
Mold needs to be entirely eradicated; otherwise, it will grow right back. This means that you have to clean far below the visible areas of growth with the right penetrating biocides.
There are some cases where you could simply spray moldy drywall with a mold stain remover. Clorox Clean Up is cheap and works well, but there are many others. You can use mold stain remover when the black mold is a simple “surface mold” caused by humidity.
When in doubt, consult a mold inspector and remediation expert for accurate assessment. During a mold inspection, professionals can analyze mold spores to determine the age of mold, and help you understand if it's inactive mold or a breed that's experiencing active mold growth.
Hydrogen peroxide, commonly used to disinfect wounds, is active against a wide variety of micro-organisms including mold. It acts by releasing oxygen at a rapid rate, which kills mold by oxidizing the surface and breaking down proteins and DNA.
Black mold contained to a limited area, such as a stain on the bathroom ceiling or wall, you can attempt to remove it on your own. However, if the mold has spread to large surfaces or the infestation is severe, you should seek professional assistance to ensure safe and effective mold removal.
According to the EPA, homeowners can remove mold on drywall under 10 square feet, but larger areas may require professional assistance.
Can Mold Inside Walls Make You Sick or Does It Need to Be Exposed? Yes. Even if you can't see it, mold can make you sick. Spores can spread throughout your home, even from relatively contained areas like inside the wall.
While it's very dark, it's not a single color, as the name implies. Instead, black mold is actually very dark green, brown, or black and is wet, shiny, and slimy. Black mold often looks fuzzy. It tends to form clusters of circular spots that may have fuzzy white edges and when wiped, leaves a green stain behind.
Extent of Water Exposure
Minor exposure can be remedied through proper drying techniques. However, if the drywall has been soaked or submerged, especially for a prolonged period, replacement is often the best option. Prolonged water exposure can weaken the structural integrity of the drywall.
A single water leak can lead to mold growth if not fixed quickly. Mold loves moist places and can start growing in 24 to 48 hours. Even small water damage can cause mold to grow. It's key to fix water damage fast to lower the water leak mold risk.
If it is moldy, there has been enough water/moisture to ruin the drywall, even without the presence of the mold. The mold has warned you to replace it.