Still, mold can hide within your home's crevices. So watch for telltale signs in addition symptoms such as unexplained runny noses, teary eyes and wheezing. "That mildewy odor is an indication," says Jeff Bishop, technical advisor to the non-profit Institute of Inspection, Cleaning and Restoration Certification. "Mold digests its food outside its body and then absorbs the nutrients through its cell wall. We digest inside our bodies, and in polite company we don't smell those gases. But molds are not that polite."