What are common signs of mold presence in a building?

The presence of visible mold growth and musty odors are classic indicators of mold in a building. Mold often appears as discoloration on walls, ceilings, or other surfaces, which can range in color from white to green, black, or even more vibrant hues depending on the species. These visual signs are typically accompanied by a distinct, earthy smell that is commonly described as musty. This odor arises from the metabolic processes of mold as it breaks down organic materials.

Recognizing these signs is crucial for early identification and remediation efforts before the problem becomes more severe and potentially harmful to health. Mold thrives in environments that are damp and poorly ventilated, so the presence of visible growth and noticeable odors serves as an important alert to building occupants and inspectors alike.

The other options do not correlate with common signs of mold. For instance, excessive ventilation can actually help prevent mold growth by maintaining low humidity levels. High air conditioner efficiency suggests proper functioning, which can contribute to controlling moisture and thus limit mold growth. Brightly colored walls are merely an aesthetic choice and do not indicate anything about mold presence or absence.