The first noticeable signs of a mold infestation will be through your senses. First will be unusual stains or discolorations. Second will be a musty smell. Here are some other signs you should keep an eye out for:

1. Damage to paint or wallpaper: mold often form colonies inside wall cavities. Once mold takes hold, it causes materials to decay and separate.
2. Damage to flooring: You might see linoleum or sheet flooring discoloring or lifting. There might also be stains on carpet or lifting of hardwood floors.
3. Stains on ceilings: Mold will form in attics or between floors. It will leave evidence such as staining on the ceiling.
4. Odor in enclosed areas: If you open a closet or crawlspace and it lets out a smell like stagnant water, that’s usually a clear sign of mold spores. Smell is an early warning sign of mold issues.