The term "Chinese Drywall" refers to drywall imported from China from 2001 to 2007 which emits sulfur gasses which usually (but not always) create a noxious odor and corrode copper and other metal surfaces, thereby damaging your air conditioner, electrical wiring, copper plumbing, appliances and electronics. Corrosion of electrical wiring can hamper the effectiveness of your smoke detection and can create a risk of fire.
Chinese drywall is also very friable, which means it is in a state where small particles can easily become dislodged with little friction, thus enabling them to easily enter your lungs. For this reason, even after Chinese drywall is removed, the toxic drywall particulate may remain unless property removed.
Hundreds of millions of sheets of Chinese drywall were imported from 2004 to 2006, but Chinese
drywall has recently been found in homes built or remodeled as early as 2001. Accordingly, this
phenomenon cannot be explained solely by the shortage of American-manufactured drywall. The presence of Chinese drywall has been reported in 37 states, the District of Columbia and Puerto Rico is estimated to have been installed in over 100,000 homes in the United States. Unfortunately, this does not paint an accurate picture as most affected homes have a mixture of safe and tainted drywall.
Chinese drywall is 1/2" in width, although Lori A. Streit, Ph.D., from Unified Engineering, the same compounds found in problematic Chinese drywall and the same gases released therefrom have also been found in drywall measuring 5/8" (which is typically used in ceilings). Chinese drywall is typically mixed in with untainted drywall, which is why people should not assume that their home is fine if they find U.S. drywall. Moreover, U.S. drywall may have been manufactured in China and rebranded.
Does your home smell like rotten eggs or ammonia (sometimes a sweetish smell)? Is it more
noticeable when entering your home and then seems to dissipate? The level of odor varies greatly in each home as does each person's ability to detect the odor. Of course, the strength of the odor also depends on how much drywall was used in the home. Significantly, some homeowners report no smell, but their home clearly has Chinese drywall. In short, do not rely on your nose alone, particularly since many develop olfactory fatigue after being exposed to Chinese drywall.
One of the telltale signs is corrosion/pitting of the air conditioner evaporator coils (which are located inside the air handler). Many owners are first advised of a freon leak, and as the corrosion progresses, evaporator coils eventually need replacement. An examination of the coils typically reveal a black sooty deposit, which may also appear on the freon line.
Chinese drywall also corrodes electrical wiring. Signs of an electrical problem include a circuit breaker which frequently needs resetting without an apparent cause (particularly a GFCI or AFCI); lights that flicker without any apparent cause; bright flashes or sparks anywhere in your electrical system (this may indicate arcing conditions in the wiring); buzzing from electrical systems, switch plates, dimmers and outlet covers that are discolored from overheating; and a smell from overheating plastic.Personal property such as precious metals and mirrors also were affected.
Many of the occupants of these homes complained of respiratory problems including sore throats, coughs, nose bleeds, and sinus headaches.
The Consumer Product Safety Commission serves as the lead agency within the interagency task force that also includes the U.S. Environmental Protection Agency, the Centers for Disease Control and Prevention/Agency for Toxic Substances and Disease Registry, and the U.S. Department of Housing and Urban Development as well as the Florida Department of Health, the Louisiana Department of Health and Hospitals and the Virginia Department of Health, among others.
On April 2, 2010, The U.S. Department of Housing and Urban Development (HUD) and the Consumer Product Safety commission (CPSC) issued interim remediation guidance to help homeowners. The guidance issued does outline a very common sense approach that simply entails removing the source of the problem (the defective drywall) and replacing the components that are affected. Consumers are cautioned to be wary of companies and contractors offering these services. Not only should consumers verify that the contractor is licensed and insured, consumers are encourage to hire a non affiliated third party inspector to oversee and document the remediation process.
Due to the dangers involved, consumers should exercise caution when inspecting components for symptoms of defective drywall. Always consult a qualified technician or experienced Inspector to inspect air conditioning and electrical components. Equally important is that consumers should recognize that many homes do display symptoms similar to defective drywall. Only a trained and experienced Inspector can recognize the distinct differences between components affected by gases produced by defective drywall and components affected by natural volatile gases that already exist in many homes.
These are the following steps that a qualified Inspector should be doing when inspecting a property for Chinese Drywall.
Step 1: Threshold Inspection
This is a basic visual inspection of the home's copper g round wiring and the air conditioning system's copper evaporator coils. The Inspector must be experienced enough to determine if any corrosion of these components is caused by gases from Chinese Drywall or if the problem is caused by natural volatile gases that exist in the home. If the Inspector does not have extensive experience and exposure to both types of situations, there is a much greater risk of the home being misdiagnosed.
The second part of the threshold inspection (visual) is to confirm that the home had drywall installed between the years of 2001 and 2008.
If the threshold inspection determines the potential presence of Chinese Drywall your Selling Agent should ammend the contract and extend the inspection period required to determine any deficiencies with the property to at least a 60 day period.
Step 2: Corroborating Evidence
It should be noted at this time that the steps described within step 2 are recommended by the CPSC and HUD ONLY if both parts of the Threshold Inspection are confirmed to be positive.
Collecting corroborating evidence combines a visual inspection along with invasive examination of the home's installed drywall. There are (6) items of corroborating evidence that are recommended to confirm homes that are considered positive through the threshold inspection.
If the home's drywall was installed between 2005 and 2008, only (2) items are required. For installations between 2001 and 2004, at least (4) if the items must be met. Consumers should note that these items may often require specialized instruments, laboratory testing, or completion by a trained professional.
(a) Testing by placing copper coupons in the home for a period of 2 weeks to 30 days or confirmation of the presence of sulfur in the blackening of the ground wires and/or air conditioner evaporator coils. The risk of placing copper coupons in the home is that the copper coupons must be placed within the walls that contain defective drywall. Most homes built during the time period were built with at least two and sometimes three different brands of drywall. Positive identification of the wall must be confirmed for accuracy.
(b) Confirmed markings of "Chinese" origin. Please use caution. Most markings found in homes that are positive for Chinese Drywall do have markings visible with specialized cameras, however an experienced Inspector must be consulted to determine accuracy when matching these markings with the brands of drywall suspected of being defective.
(c) Strontium levels in samples of drywall core found in the home. This may require laboratory testing for accuracy. There are portable machines available to utilize, however consumers are cautioned to ensure that the person using these portable machine is properly licensed and that the machine is registered. Care should be taken to examine every wall of the home in order to ensure accuracy (for the same reason noted above where multiple brands of drywall may be installed in the home).
(d) Elemental sulfur levels in samples of drywall core found in the home exceeding 10ppm. Again, this method is only accurate if the correct sample of drywall is taken. Due to the high probability of multiple brands of drywall being installed in the home, multiple core samples may need to be tested. This method is costly at a testing price range of $200-$500 per sample.
(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. This method is much like item (d) explained above and also has the same risks of false reporting if the incorrect piece of drywall is chosen to sample.
(f) Corrosion of copper metal to form copper sulfide when copper is placed in test chambers with drywall samples taken from the home. This method is a duplicate of method (a), however is performed in a laboratory. Again care is required to remove the correct sample of drywall in order to prevent false reporting.
Users should also be aware that the corroborating evidence items (c), (d), (e), and (f) often take weeks to obtain results. For homeowners living in these conditions and buyers under contractual obligations for inspections may not be able to tolerate the turnaround time.
In conclusion, a comprehensive visual inspection with the invasive, yet non destructive corroborating evidence is sufficient to identify homes that contain defective drywall (Chinese Drywall).