When gutters malfunction, water cascades over parts of the home that were never designed to withstand exposure to that much moisture. Because they're made of wood—and therefore susceptible to rot—trim elements like windowsills and door jambs are often the first to buckle. Once that happens, it doesn't take long for storm water to find its way into the home. As it infiltrates unseen areas behind walls and beneath flooring, moisture inevitably leads to the growth of mold and mildew. Not merely unsightly (and often quite smelly), mold poses a legitimate health hazard, particularly if anyone in your household suffers from allergies. And though it's possible to get rid of mold, remediation doesn't come cheap—far from it, in fact.