Q. What is “Chinese drywall?”
A. “Chinese drywall” is also referred to by various other names such as imported drywall, defective drywall, corrosive drywall, and tainted drywall. We use the term Chinese drywall in this blog simply because that name is the most widely recognized. In simplest terms, Chinese drywall is any drywall that emits harmful reduced sulfur gasses.
Q. When was Chinese drywall installed?
A. Confirmed cases of Chinese drywall have shown that it was installed between 2001 and 2008.
Q. How will Chinese drywall affect my home?
A. The reduced sulfur gasses emitted by Chinese drywall corrode copper, silver, and chrome in the home such as in appliances, air conditioning systems, electrical wiring, plumbing, bathroom fixtures, mirror backing, and jewelry. This eventually results in premature failure of appliances and air conditioning systems, safety hazards from the electrical and plumbing systems, and cosmetic damage to the bathroom fixtures, mirrors, and jewelry.
Q. Is Chinese drywall harmful to people?
A. Residents of homes with Chinese drywall have reported a variety of health effects including irritation of the eyes, respiratory system, and skin. However there have not been any studies that clearly define the health effects of Chinese drywall. The Florida Department of Environmental Health stated “The symptoms reported by occupants are not unique or consistent across affected homes.”
Q. Who regulates Chinese Drywall?
A. There is no entity specifically responsible for regulating Chinese drywall. As such there has been a lot of misinformation presented by the news media and self-proclaimed “experts” in the field. The Consumer Product Safety Commission (CPSC), Department of Housing and Urban Development (HUD), Florida Division of Environmental Health (FDEH), and the United States District Court have published recommendations for identifying and remediating Chinese drywall.
Q. What makes Chinese drywall different from North American drywall?
A. Chinese drywall contains elevated levels of “elemental” sulfur (Orthorhombic cyclooctasulfur sulfur, “S8″) which contributes to the emission of the harmful reduced sulfur gasses.
Q. What are reduced sulfur gasses?
A. Carbon disulfide (CS2), hydrogen sulfide (H2S), and carbonyl sulfide (COS).
Q. Is all sulfur in drywall bad?
A. No. All drywall contains significant quantities of sulfur. It is only the elemental sulfur that causes a problem. The CPSC, HUD, and FDEH have recommended a threshold of 10 mg/kg (ppm) of elemental sulfur be used as a criteria for identifying Chinese drywall. Some confirmed cases of Chinese drywall have shown elemental sulfur concentrations as high as 2500ppm or more while North American drywall typically contains less than 2ppm of elemental sulfur.
Q. How is Chinese drywall marked?
A. Some Chinese drywall is clearly labeled with “Made in China”. Some has distinctive markings and/or text on the end tape. Some do not have any markings at all. Even if markings are present, laboratory testing must still be performed for confirmation.
Q. Who are the known producers/distributors of Chinese drywall?
A. The known producers/distributers include:
- Bedrock Gypsum
- Beijing New Building Materials Co. Ltd. (BNBM)
- Crescent City Gypsum, Inc.
- Dragon Brand Drywall
- IMG Drywall
- International Materials Trading (IMT) Gypsum
- Knauf Dongguan
- Knauf Plasterboard (Tianjin) Co., Ltd.
- Knauf Tianjin
- Knauf WuHu
- Public Limited Co.
- Shandong Chenxiang GBM Co. Ltd. (C&K Gypsum Board)
- Shandong Taihe Dongxin Co., Ltd.
- Taian Taishan Plasterboard Co. Ltd.
- Taishan Gypsum Co., Ltd.
- Venture Supply Inc.
The US District Court has compiled photographic examples of Chinese drywall markings at:www.laed.uscourts.gov