What Is Chinese Drywall? Inspection

Chinese drywall is the name given to defective and contaminated drywall that pollutes homes by off-gassing sulfide and disulfide compounds. Not all drywall from China is defective and not all known defective drywall is Chinese. Non-Chinese drywall that is defective is thought to be recycled drywall that is reprocessed and resold in the US. While contaminated drywall was importated in 2001, the majority was imported between 2004 and 2007. Homeowners in 41 states report having contaminated Chinese drywall and complaints have been filed in 21 states.

The majority of drywall entered the US through Florida, California, Louisiana, and Virginia. Much of the contaminated drywall was used in rebuilding areas after catastrophes such as hurricanes and areas with the biggest boom in housing. Most Chinese drywall was imported from six factories in China located in Beijing, Dongguan, Wuhu, Tianjin, Taian, and Shandong. The large manufacturers of Chinese drywall are Knauf Plasterboard Tianjian and L&W Supply Corp, Beijing New Building Materials, Taian Taishan Plasterboard, and Taishan Gypsum Co.. Since 2006 alone more than 550 million pounds of drywall was imported from China. The contaminated Chinese drywall problem was first reported in December, 2008.

Contaminants in the drywall include several sulfide and disulfide compounds, including hydrogen sulfide, strontium sulfide, and carbon disulfide, among others. The origin of these contaminants is not known, but is thought to be from mined gypsum, coal fly ash, or radioactive phosphogypsum. Contaminated drywall off-gases compounds into the air as a function of heat, humidity, and the amount of defective drywall in the building. Indications of contaminated drywall include a foul sulfur smell similar to rotten eggs or used fireworks, black corrosion of copper and other metals, and nosebleeds and respiratory problems.

How Did This Happen?

In the early to mid 2000s, demand for building materials grew enough to cause a shortage of domestic supply. When the housing boom was compounded by several major natural disasters, including Hurricane Katrina, the domestic supply of drywall was depleted and distributors looked for alternative sources. During the housing boom parts of the country experienced a shortage of building materials. Contractors were forced to source materials from alternative sources. In 41 states, including Florida, Louisiana, California, Virginia, Mississippi, Alabama, North Carolina, and Washington, distributors sourced drywall from China. The use of Chinese drywall was not for price or quality reasons, but purely caused by a lack of supply.

How Big Is The Problem?

At this point, no one is sure. Homeowners in 41 states report having contaminated Chinese drywall. In Florida alone, more than 550 million pounds of Chinese drywall were imported since 2006 – enough to build 30,000 homes. Complaints of odd smells in homes and unusual failures of copper coils were reported for years, but the cause was only recently discovered. Contaminated Chinese drywall is most common in areas that experience building growth spurts, such as the post-Katrina Gulf area and Florida in the housing boom. Chinese drywall is also widely found in large scale projects, including apartment complexes and townhomes.

What Are The Signs and Symptoms Of Chinese Drywall?

Contaminated drywall may corrode copper HVAC coils, refrigerator coils, mirrors, silver jewelry and utensils, and copper ground wires. The drywall may or may not emit an odor and may or may not cause health effects. Because it is sensitive to heat and humidity, a problem may not show until the hottest time of year. As few as three sheets of Chinese drywall in a home is enough to require remediation.

Signs you may have Chinese drywall in your home:

  • Sulfur odor similar to rotten eggs or used fireworks
  • Electrical problems in the home
  • Black corrosion on copper or other metals
  • Failure of relatively new HVAC systems or refrigerators
  • Circuit breakers tripping without reason
  • Knauf or Made in China printed on the back of drywall
  • Respiratory problems
  • Frequent nosebleeds
  • Feeling lightheaded or dizzy

What Are The Health Effects?

The EPA and the Florida Department of Health are conducting studies on the health implications of contaminated Chinese drywall. To date they have not drawn any definitive conclusions. Homeowners with contaminated Chinese drywall consistently report some or all of these symptoms: headaches, lightheadedness, frequent nosebleeds, and upper respiratory issues. Long-term health effects are not known. The health issues appear to go away after moving out of the residence with contaminated Chinese drywall. It is unknown whether sensitivities similar to mold develop.

Below you will find a link to a report by the Consumer Product Safety Commission and the Department of Housing and Urban Development that has the most current guidelines on identifying defective drywall.


See below link for a recently published criteria for establishing a Import drywall case


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