Mold growths, or colonies, can start growing on a damp surface in 24 to 48 hours. They reproduce through spores (tiny, lightweight “seeds”) that travel through the air. The time it takes for mold to grow and appear depends on the mold species, the material it grows in and the amount of moisture it has, among other things. Given the right conditions, mold will begin to germinate and grow as soon as 24 hours after encountering the moisture source.
In 3 to 12 days, mold spores will colonize. In 18-21 days, mold may become visible. Under ideal conditions (optimal temperature and humidity level), it takes 24 to 48 hours for mold to germinate and grow. Spores usually begin to colonize in 3 to 12 days and become visible in about 18 to 21 days.
Of course, the time varies according to the different types of mold and depends on the actual conditions of the house: the type of household surfaces and materials in the affected area, the amount of moisture, the ambient temperature, etc. However, the more time passes, the greater the chances that mold will develop and spread to other areas of the house. It usually takes 24 to 48 hours for mold to grow after leaving water on the surface. This can quickly turn into a major mold problem in a couple of weeks, depending on whether the conditions are still right for mold to grow.
Mold spores are usually visible after 18 to 24 days. As a general rule, mold will begin to grow within 24 hours after moisture is introduced into the air. When it comes to repairing water damage, time is of the essence. If you wait too long before asking a professional for help, mold and mildew may spread beyond repair.
The distinctive smell of mold usually appears within 48 hours after a flood or other mishap involving an influx of moisture or water. However, it may not always appear right away. Slower-growing molds (such as Stachybotrys) usually take months to grow and are often difficult to detect initially.