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Chinese Drywall Syndrome and what You Need to Know

Chinese Drywall Syndrome is an issue that occurred with certain imported drywall from China beginning in 2001 going through 2009 and was first investigated by the CPSC and identified as a problem in 2008. During this time there was a huge increase in demand for drywall not only from the housing boom of the mid 2000’s but from all the hurricanes that rattled the Gulf Coast during that time. Rebuilding efforts diminished domestic supplies even further and home builders, contractors and suppliers began to import drywall from China by the millions of sheets.

What’s the Problem with Chinese Drywall?

It wasn’t long after the drywall began to be used that problems in the home began to arise. The first thing most homeowners noticed was a strong smell of what was described as being like rotten eggs or like when matches flare up. Namely, a sulfurous smell. Many times there is no noticeable smell. Often, home-owners are unaware they have a Chinese drywall problem until they go to sell and it is uncovered during the buyer’s inspection. Sometimes sellers are aware and attempt to cover up by cleaning evaporator coils and exposed copper wires, etc…

And these homeowners were onto something. Sometimes within just a few short months of moving in and running their AC units, the systems would fail. As the techs came in to fix the problem they noticed that the coils had become completely corroded with a black color. Sulfurous compounds are the only thing that can corrode copper to black like that.

At first, people could not figure out where the sulfur was coming from. Was it in the water? Was there a gas leak? Some natural source? Soon, it was discovered that the drywall was the culprit. The drywall cores contained large amounts of hydrogen sulfide, carbonyl sulfide, carbon disulfide, and strontium. This drywall would offgass these sulfurous compounds into the atmosphere of the home, giving it its characteristic smell, and corroding any exposed copper, and some other metals.

Homeowners had appliance failures, corroded electrical wiring, smoke alarm failures, and HVAC system trouble. Even if the coil in the HVAC system was replaced, it would quickly fail again. Word quickly spread and the problem became well-known.

In order to diagnose your house as having the problem drywall first a threshold inspection of a smell and visible corrosion on exposed copper must be done. After that a home inspector will issue corrosion testing strips and take a look at the back of the drywall for manufacturers markings. This step is called the “Corroborating Evidence” step in the event the “Threshold inspection” is positive for possible problem drywall and when legal action by the home owner is initiated. (Note: not all problem drywall will have markings on it.) If those are positive hits then they will send off samples of the drywall cores for further testing.

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