Where to Look for Mold
Mold grows on organic materials, such as paper, dirt, wood and soap scum. Mold grows on moist materials, so mold growth is likely in areas wet by water leaks, flooding, humidity levels above about 70 percent and condensation. Any flooded area that was not completely dried within about one day is likely to have mold growth. Walls need to be opened and rapidly dried to prevent mold growth. Any area that is stained from water should be examined for mold growth. Peeling paint may be an indication of wet walls.
Moisture seeping through concrete walls and floors will cause moist conditions likely to cause mold growth on or in walls, carpeting and materials stored in the basement. Mold often grows under cabinets, behind base-boards, inside walls, in carpet padding and under vinyl wall coverings.

An unvented clothes dryer creates a very humid, warm environment conducive to mold growth. Closets may have mold growth if clothing is damp or if there is a cool outside wall in the closet. Also, there is a chance mold might be growing behind furniture, particularly against an outside wall.
Mold will not normally be found in furnace or air-conditioning ducts unless they were flooded because the heated or air-conditioned air is very dry.
Moisture coming through a basement floor or wall may deposit a light-colored salt and other minerals that are sometimes thought to be mold. The deposits should quickly dissolve and disappear when wet with water if they are a salt.


Mold Removal
Since people react to mold whether it is living or dead, the mold must be removed.
Take steps to protect your health during mold removal. Use a mask or respirator that will filter out mold spores. Usually it will be designated as an N95, 3M #1860 or TC-21C particulate respirator. Wear eye protection, rubber gloves and clothing that can be immediately laundered.

Dampen moldy materials before removal to minimize the number of airborne mold spores.
Mold can be removed from hard surfaces such as hard plastic, glass, metal and counter tops by scrubbing with a non-ammonia soap or detergent. (Do not mix ammonia and bleach; the fumes are toxic.)
It is impossible to completely remove mold from porous surfaces such as paper, Sheetrock (drywall) and carpet padding, so these materials should be removed and discarded.
 
Scrubbing may not completely remove mold growth on structural wood, such as wall studs, so it may need to be removed by sanding. Wear personal protective gear and isolate the work area from the rest of the home.