The toxic mold issue gained national attention when activist-turned-celebrity Erin Brockovich testified before the California legislature in 2001 that she, her husband, and their three children were battling mold-related illnesses due to fungus that had contaminated their home. Since then, homeowners everywhere have been curious about the more that 100,000 species of mold that contaminate homes and can cause damage to the lungs and nervous system.

In fact, one of most toxic molds, Stachybotrys (pronounced “stack-e-botris”), has been found in all 50 states and grows in areas that are wet, including in leaky plumbing, sewer backups, and even around frequently overflowing washing machines. Unlike, Stachybotrys, most molds are not hazardous to you if you are healthy. Too much exposure to most molds, however, may cause asthma or hay fever or serve to worsen other existing symptoms, according to experts.

Even if mold in your home does not cause health problems, it establishes itself in the wood of your home, causing “dry rot.” This can quickly turn a homeowner’s worst nightmare into a devastating reality.

Dead mold eventually causes wood to dry and shrink, breaking up into irregular chunks. Cracks in the wood then act like straws, siphoning up moisture and carrying it to the undamaged portions of wood. Left unchecked, this process keeps recurring, continually rotting more wood, and can cause severe structural damage to your home.

Even so, insurance companies typically consider mold damage a home maintenance problem and, consequently, it is excluded in standard home insurance policies, which cover mold damage only if it is the result of a covered peril, such as a burst pipe. Mold caused by water from humidity, leaks, condensation, or flooding is excluded from coverage.

Adding insult to injury is the fact that mold claims cost insurers more than $1 billion in 2001, approximately five times the cost in 2000, according to the Insurance Information Institute. As a result, home insurers are raising their premiums and most are excluding mold altogether.

A handful of insurers now offer riders that allow you to purchase some degree of mold coverage. For information about mold coverage in your home insurance policy, ask your personal insurance agent.