Molds are part of the natural environment.
Molds produce tiny spores, and these spores waft through the indoor and outdoor air continually. When mold spores find a damp spot indoors, they usually start digesting whatever they land on in order to survive. There are molds that can grow on wood, paper, carpet, and foods. When excessive moisture or water accumulates indoors, mold growth will often occur, particularly if the moisture problem remains undiscovered or unaddressed. Water can come from many sources but usually comes from:

1. Rain water (or flood),
2. Plumbing supply lines,
3. Plumbing waste lines and
4. HVAC condensation pans and lines that are stopped up.

I hope you find the following helpful. You will find additional information on the websites and booklets cited at the bottom of this page.