Should I be concerned about mold?

By: Dian Hymer

December 30, 2002

Recently the purchaser of an Oakland, Calif., townhouse discovered he had a leaky skylight. While repairing the interior damage caused by the leak, he found mold growing inside the walls. What started as a simple repair turned into a complicated and costly abatement project.

Another prospective buyer, who'd heard about toxic mold, had the Piedmont, Calif., home he intended to buy tested for mold before he removed his inspection contingency. There were no visual signs of mold, but there was a musty odor in the downstairs of the house. The buyer paid about $600 to have air samples collected, which revealed that toxic mold was indeed present.

The buyer decided to go through with the purchase, but only after he talked with several contractors about how to deal with the problem. The seller agreed to lower the purchase price for the buyer to help offset the cost of mold remediation.

Mold is the latest environmental hazard issue to concern the residential housing industry. It's not the first. In the early 1980's, people were hysterical about asbestos in the home. The advice from professionals at that time was to hire environmental hazard abatement contractors to get rid of the stuff. Years later, it was decided it was risky to remove asbestos from a home. Now, in many cases, the advice is to seal the asbestos in place, if it's in good condition.

The mold issue is new. And, there is a high level of concern about the subject. It's understandable if you consider recent news stories of homeowners who had to vacate their homes because they became sick after they discovered mold growing in their home. Occasionally you hear about mold contamination that's so intrusive that an entire structure must be demolished to remove the problem.

There is a lot we don't know about mold. But, here's what we do know. Mold and mold spores are virtually everywhere; there is no practical way to completely eradicate mold in a home. Some people are allergic to mold. And there's anecdotal evidence to suggest that toxic molds may be a bigger health concern. But currently, there are no Environmental Protection Agency (EPA) standards to indicate what is considered a safe, or unsafe, level of airborne mold contaminants.

HOUSE HUNTING TIP: As a homeowner or potential home buyer, you should be aware of the potential hazards related to mold so that you can make an educated decision about what to do about the problem. Mold does not grow in dry, well-ventilated places. Mold requires moisture to grow. The key to controlling indoor mold is to control the moisture in your home.

Leaky pipes, roof leaks, drainage problems, leaky doors and windows, and showering without opening a window or using an exhaust fan can all lead to moisture buildup and mold growth. According to the EPA, mold can be washed off hard surfaces using detergent and water. Absorbent materials that become moldy, such as sheetrock, carpet and ceiling tiles, may have to be replaced in order to get rid of the problem.

The EPA recommends lowering the humidity level in a home to the 30-60 percent range in order to decrease mold growth. This can be achieved by venting bathrooms and dryers to the outside, using air conditioners and de-humidifiers, increasing ventilation (for instance, in a basement or crawl space), and using exhaust fans when cooking and dishwashing.

The best defense against mold contamination is to be proactive and take steps to reduce the moisture level in your home.

THE CLOSING: For more information about mold, visit the EPA Web site at www.epa.gov. Enter "mold" in the search box and select "go."

Dian Hymer is author of "House Hunting, The Take-Along Workbook for Home Buyers," and "Starting Out, The Complete Home Buyer's Guide," Chronicle Books.