Q: I own a townhouse condo with Spanish-style roof tiles. I had two holes in my roof that were patched and 20 tiles that were reset. I had a significant leak from the roof, which caused the air conditioning unit inside the house to overflow, thus creating mold (Stachybotrys and others) in the roof, a/c and adjoining bathrooms.

The mold inspector stated that it was clearly evident that the roof leak caused a cascade event. One of the industrial hygienists from the insurance company also noted roof damage.

The condo insurance company stated that 1) The roof leak caused no damage and 2) I spread the mold because I had one of the bathroom walls torn down. My opinion is that it is unbelievable that the roof caused no damage whatsoever.

I am trying to find an expert witness that can reassess the damage from the roof and state that it was, indeed, a cascading event. The inspector is giving a written statement to this effect.

Do you know of anyone who may be able to help me?

A: The term "cascading event" shows up an awful lot when we talk about mold contamination. This is probably because the presence of excess moisture or live water is necessary to support mold's growth, and because water doesn't just happen.

Based on the rather brief description of the problems, it does appear that some leaks from the roof may have started the problem. Without actually being on-site however, it's difficult to say how or why the roof leak caused the air conditioner to leak. But your letter does cause me to consider several issues.

The presence of Stachybotrys mold spores indicates a long-term water leak that most likely affected drywall in the bathroom. This type of mold doesn't grow overnight, and some indication of water leaks or moisture damage should have appeared long before the mold. That said, however, moisture in an attic area and interstitial wall spaces can go unseen for months.

The condo insurance company stated that the roof leak caused no damage. What they could mean is that there's no discernable damage directly below the area of the leak. What we occasionally see, however, is that water will travel horizontally, sometimes over a very long distance, before actually dripping onto a lower surface. Water does leave streaks, though, and evidence of the leaks should be clearly evident on the rafters or ceiling joists.

They also said that you spread the mold by tearing one of the walls down. I can't argue with that. We often see cases where an unsuspecting homeowner opens a wall cavity to inspect or remodel, and winds up creating a mold hazard.

You certainly can spread mold spores throughout a home by simply removing a mold-contaminated wall panel. If this was done by a remodeling contractor, he/she should have been aware of the hazard, and should have been prepared to handle the consequences. If you did this remodeling yourself, you carry the blame. Regardless of that, the mold was there, and should not have been. Someone - perhaps the condo insurance company - should be held responsible.

Finally, your request for an "expert witness" indicates that you plan to sue. If you're suing to prove that this was a cascading event, as your inspector says, why not use him as your expert witness? Professional real estate inspectors have to be licensed by the state in many jurisdictions. Perhaps Florida is one of those areas. If it is, then the opinion of your inspector is as good as any. That leaves it up to the other side to provide an expert who has as much experience or is as good at discussing the issue and problems as your expert.

Whatever you choose to do, make sure you document the process and make the repairs immediately. You can sort out the minutiae later.

Travis West is the president of Building Air Quality Inc., a Houston-based indoor air quality consulting firm. He can be reached at twest@baq1.com, or toll-free at 866-367-1177.

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