A specialized task force headed by the Department of Housing and Urban Development (HUD) and the Consumer Product Safety Commission (CSPC) developed a system of criteria to use in identifying houses affected by defective Chinese drywall. The Federal Interagency Task Force on Problem Drywall is recommending steps for identifying the defective drywall manufactured in China and used to build homes during the housing boom. The two-step identification process begins with an initial inspection to find visual signs of metal corrosion and evidence of drywall installation during the time when the defective drywall was used. In its summary (download here), the task force recommends looking for the blackening of copper electrical wiring and/or air conditioning evaporator coils as well as determining if the drywall was manufactured between 2001 and 2008. If the home in question meets the first two criteria, the task force said further inspection is necessary because metal corrosion in homes can happen for other reasons. The task force said homes with Chinese drywall have two of the following supporting characteristics:

(a) Corrosive conditions in the home, demonstrated by the formation of copper sulfide on copper coupons (test strips of metal) placed in the home for a period of two weeks to 30 days or confirmation of the presence of sulfur in the blackening of the grounding wires and/or air conditioning coils (b) Confirmed markings of Chinese origin for drywall in the home (c) Strontium levels in samples of drywall core found in the home (i.e. excluding the exterior paper surfaces) exceeding 1200 parts per million (ppm) (d) Elemental sulfur levels in samples of drywall core found in the home exceeding 10 ppm (e) Elevated levels of hydrogen sulfide, carbonyl sulfide and/or carbon disulfide emitted from samples of drywall from the home when placed in test chambers using ASTM Standard Test Method D5504-08 or similar chamber or headspace testing (f) Corrosion of copper metal to form copper sulfide when copper is placed in test chambers with drywall samples taken from the home

The recommendations follow a CPSC study of 51 homes in Florida, Louisiana, Virginia, Alabama, and Mississippi. The dominant types of corrosion found were copper sulfide and silver sulfide, which appear as a black coating on copper or silver metal. As HousingWire previously reported, not all drywall manufactured in China is defective. Louisiana attorney general James Caldwell filed a lawsuit against 23 companies alleged to have been involved in the manufacturing, distribution or installation of Chinese drywall that was used to rebuild homes after hurricanes Katrina and Rita. The Chinese drywall problem has sparked a number of additional lawsuits against builders, manufacturers, distributors and insurance companies. A consumer advocacy group recently formed to represent homeowners affected by Chinese drywall. According to local news reports in Florida, there is a growing concern that the drywall’s prevalence in Florida communities built during the housing boom will face further additional price declines because of the defective materials. State lawmakers are trying to help affected homeowners. In Virginia, the state Senate passed Senate Bill (SB) 298, which would prohibit insurance companies from raising rates or dropping homeowners whose homes were built with Chinese drywall. The Virginia House of Representatives is considering a similar bill, House Bill (HB) 45. Write to Austin Kilgore.