Owners of homes and other buildings containing Chinese drywall now have a clear directive from the federal government: Tear out "all possible problem drywall" and replace it, the U.S. Consumer Product Commission and Dept. of Housing and Urban Development advised on April 2.

Photo: CPSC

Homeowners should replace Chinese drywall (slightly gray in color) with new wallboard (white in color), federal agencies say.

In addition, owners should replace all electrical systems, gas piping, sprinkler systems, smoke alarms and carbon monoxide alarms, whose metal components corrode under high levels of hydrogen sulfide. Who will pay for the work remains unclear, but total losses and litigation could cost in excess of $25 billion nationwide, according to New York-based consulting firm Towers Watson. It released that estimate last summer, while complaints to the CPSC have continued to rise.

Of today's 3,000-plus complaints, more than half are in Florida (59%), followed by Louisiana (20%), Mississippi (6%), Alabama (4%) and Virginia (4%). The government is not advising owners to replace copper-water lines or heating, ventilating and air-conditioning equipment "because of the absence of a direct connection to safety." However, studies show that those systems may also corrode and fail.

Drywall manufactured in China between 2005 and 2006 was found to emit 100 times more hydrogen-sulfide gas�which attacks metal and in some cases smells like rotten eggs�than non-Chinese drywall. Between 2004 and 2007, the U.S. imported more than 550 million lb of Chinese drywall, reports the National Association of Home Builders. Remediation could cost as much as $100,000 per house, builders say.