By Jim Cory. When you tear up the bathroom floor and find mold, it's tempting to just ignore it. But unless you identify the point where water enters or the source of excess humidity -- two common reasons mold grows -- simply repairing and replacing the floor leaves the homeowner uninformed and the mold to fester.

Ignorance is not bliss

That could prove to be a big mistake. These days, ignoring the mold you find in floors, roofs, attics, HVAC systems, or behind siding could result in a lawsuit.

D.S. Berenson of Johanson and Berenson, a Washington, D.C., law firm that often represents construction and home improvement contractors, says projects involving demolition and rebuilding "increase the exposure the contractor is going to get, as well as the potential liability." The contractor who ignores mold, attempts without proper certification to treat it, or simply doesn't recognize it for what it is, may eventually find himself in court.

Who's responsible?

According to Berenson, state and federal courts have yet to determine the extent of contractor responsibility in such situations.

His firm, Berenson says, recommends clients include language in all contracts that recognizes the potential for mold problems to occur and addresses the contractor's responsibility for it.

To start with, mold should be cited as among those conditions over which the contractor has no control. Additional information should specify what action the contractor will take in the event mold is discovered. Johanson and Berenson suggest four options:

1. Advise clients of the issue.

2. Advise clients of the issue and refer them to a remediation specialist.

3. Advise clients of the issue and require them to sign a waiver releasing the contractor from any mold-related problems in the future before the contractor will return to the site.

4. Advise clients of the issue, secure a waiver, and return to the site only after the area has been inspected and remediated.

Of these four solutions, Berenson says his firm most often recommends the last, because it's the safest. Whatever you do, don't try treating the mold yourself unless you're certified in mold remediation. "By attempting remediation without certification, you run the risk of spreading the mold and increasing the exposure."

Diana Vincenti, an attorney for DreamMaker Bath and Kitchen by Worldwide, recommends that anyone in an industry where he or she is likely to encounter mold "may want to consider getting insurance coverage, just in case you're involved in mold-related lawsuits. Carry it and make sure you understand what you can and cannot do under that coverage."