Chinese Drywall Problems and Tests

Many reports from all over the U.S. indicate that the Chinese drywall causes problems related to both the health of homeowners and the functioning of electronic appliances within the home. These Chinese drywall problems are affecting not only homeowners and potentially business owners too, but also builders and lawyers since the affected homeowners usually start lawsuits against builders and ultimately manufacturers of the defective drywall for damage compensation. In brief, the main problems with Chinese drywalls relate to the emission of potentially toxic and corrosive fumes (gases) from the drywalls into the home atmosphere (especially under higher temperatures and humidity). Such emitted fumes include, but are not limited to: hydrogen sulfide (H2S), sulfur dioxide (SO2), carbon disulfide (CS2), and possibly other irritating and corrosive fumes. These gases have an unpleasant rotten egg odor, may pose a health risk to inhabitants and seem to corrode electrical and plumbing components, determining the malfunctioning of electronic systems within the home.

There are two categories of problems with Chinese drywall – if you have experienced any of these Chinese drywall problems since moving into a recently bought home or if any of these problems got worse since moving, then you may be at risk of living in a home with defective Chinese drywall. Below are the most commonly reported Chinese drywall problems.

Chinese-Made Drywall - Health Problems

Reported health problems to inhabitants of homes built with toxic Chinese drywall vary and may include one or more of the following health Chinese drywall problems:

  • irritated and itchy eyes and skin,
  • sinus problems and difficulty breathing; 
  • respiratory infection (accumulation of a rubber-cement-like substance in sinuses)
  • nose bleeds, persistent coughing, 
  • asthma attacks, 
  • extreme fatigue, 
  • recurrent headaches, 
  • sore throat, cough, 
  • dizziness, insomnia, 
  • severe allergies, 
  • gastrointestinal problems, 
  • hair loss,
  • joint and muscle pain

Chinese-Made Drywall - Other Problems

Reported environmental Chinese drywall problems within homes containing defective Chinese drywall include one or more of the followings:

  • persistent rotten-egg smell within the house only (not outdoors)
  • corrosion of electrical and plumbing components, 
  • blackening of copper pipes and wiring, 
  • blackening of appliances containing copper,
  • silverware tarnish, 
  • black soot on the plugs of washers and dryers, 
  • black soot on the wires behind light-switch plates, 
  • blackening of metal on bathroom fixtures and of coils from air-conditioning systems, 
  • overheating of parts of electrical systems, 
  • electronics malfunction, 
  • power outages, 
  • broken air-conditioning, failure of air conditioning coils with a black residue,
  • corrosion of mirror edges, 
  • intermittent and total failure in operation of dishwashers and/or refrigerators,  broken microwave ovens, 
  • unusual sounds from electrical system devices, 
  • dim/flickering lights.

Identifying and solving the Chinese drywall problems is not happening overnight. Every day small steps forward are made increasing our awareness and testing capabilities that will ultimately solve the Chinese drywall problem. The CPSC has launched the Drywall Information Center, where consumers can report incidents. Over 4,000 reports were received from U.S. residents.

Reference Cited
CPSC. 2009. CPSC Investigation of Imported Drywall Status Report, July 2009.


Tests for Homeowners and Prospective Buyers

Here is a guide of simple things you can do yourself to test for Chinese drywall (plasterboard) before attempting more or less expensive lab tests. We recommend that you try most of the recommended Chinese drywall tests and prepare a checklist. If most of the testing for Chinese drywall indicate you are at risk, we highly recommend ordering specialized lab tests for confirmation.

“Do-It-Yourself” Testing for Chinese Drywall

Some straightforward Chinese drywall tests you can do by yourself include:

a. THE YEAR THE HOME WAS BUILT OR REMODELED: The first testing for Chinese drywall you should do is to check when the home was built and when was it last remodeled or renovated? If any of these happened in the 2000’s (2001 to present) then you are at risk of having a home with defective Chinese drywall and should proceed with the below suggested Chinese drywall tests;

b. ANY UNPLEASANT (ROTTEN-EGG) PERSISTENT ODOR INSIDE THE HOME: The next testing for Chinese drywall consists in responding to questions such as: Have you, anyone in your family or anyone visiting your home felt a strange rotten-egg-like persistent odor anywhere within the home, but which disappears when you step outside? If the answer to this Chinese drywall test-question is yes, then the air quality inside your home may be poor with a high probability of the presence of defective Chinese drywall. The off-gassing product from the defective Chinese drywall is composed of sulfur gases such as hydrogen sulfide which could create a health hazard;

c. BLACK SOOT ON THE WIRES BELOW LIGHT-SWITCH PLATES: Another testing for Chinese drywall consists of the following: Remove all light-switch plates and look inside (BUT DO NOT TOUCH ANY WIRES!) at the wires (you may use a flashlight) – if they are blackish or covered with what seems to be black soot, then you may have defective Chinese drywall; please keep in mind that the Chinese drywall may not be used in every wall of your home so you do not need to have consistent results throughout the home; even if you notice the blackish color below one light-switch plate, it is a test result indicating that you may have defective Chinese drywall in a room wall;

d. BLACK SOOT ON THE AIR CONDITIONING COILS: Another Chinese drywall test you may do involves the following: Remove the panel of your air conditioning system and look at the coils inside – if they are blackish or covered with a black soot, then you may have defective Chinese drywall;

e. FREQUENCY AND OCCURRENCE OF DEFECTIVE AIR CONDITIONING SYSTEM: Here is another easy test for Chinese drywall: if your air-conditioning system failed repeatedly or while under warranty and you need to replace the evaporator coils, it might indicate the presence of toxic Chinese drywall even without black soot observed on the coils. Additionally, a general Chinese drywall test you should do if you want to purchase a home is to inquire for any air-conditioning repair work or problems encountered by past owner(s);

f. BLACK SOOT ON THE WASHER AND DRIER PLUG: Furthermore, Inspecting the plug of your washer and dryer is another way of testing for Chinese drywall presence. If it is blackish or covered by black soot, the probability of Chinese drywall being present is high;

g. FREQUENCY AND OCCURRENCE OF ANY PREMATURE FAILURE OF ELECTRONIC EQUIPMENT WITHIN THE HOME: This Chinese drywall test refers to equipment such as TV, refrigerator, microwave oven, dishwasher, computer, cable box, coffee pot. If any electronic equipment within the home brakes down prematurely or frequently you may have defective Chinese-made drywall;

h. CORROSION OVER PLUMBING AND ELECTRICAL FIXTURES Another way of testing for Chinese drywall is looking for copper corrosion. Any observed corrosion indicates the possibility of having defective Chinese-made drywall;

i. RUSTY BATH DRAINS could also be a sign of the presence of defective drywall. Checking the bath drains is just another simple Chinese drywall test you may do;

j. PERSONAL JEWELRY TURNING BLACK: if you notice that your jewelry turns black which did not happen before or if this happens faster than before, it is a sign that it might have been exposed to various sulfur gases emitted by a defective Chinese-made drywall;

k. BRAND NAME LISTED ON THE HOME DRYWALLS: A direct Chinese drywall test is to find a spot in the home (basement or attic is recommended) where you may push the insulation around or cut a small hole and check the brand name on your drywall. This testing for Chinese drywall is LESS RECOMMENDED because it is hard to test every single drywall within your home. Additionally, not all drywalls may be labeled and even if you have Chinese drywall it may not be defective (because not all Chinese drywalls are defective or because your home may be in a favorable climate (e.g., with little heat and humidity). If you proceed with this Chinese drywall test, look for Chinese-made drywalls brands like Knauf – which was often reported with problems (about 20% of defective drywall may be associated with this brand name). Please be aware that some people reported problems with drywall made in the U.S. too, although such reporting is scarce and not necessarily confirmed. Additionally, re-labeling of original Chinese-made drywall could be the culprit. Thus, what is most important is to look for any effects of a defective drywall rather than to look for the brand of drywall itself. Note that the brand identification may be however important at a later stage if you decide to sue for damages.

l. THE SIZE OF THE DRYWALL may also be used to point out potentially defective Chinese drywalls. According to Rosen (2009), in Florida, the Chinese drywall has only ½ inch thickness and dimensions of 4' x 12'. However, the size of drywall from an already build home may not be readily available and it is not clear if this applies for Chinese drywall in other states, too. Additionally, it is possible that potentially defective drywall exists in many other sizes, thus this Chinese drywall test may not be conclusive.

m. THE COLOR OF THE DRYWALL: Checking the color of your drywall is another way of testing for Chinese drywall potential presence in your home. This is because defective Chinese drywall (e.g. the Knauf brand) was reported darker in color probably due to their higher content of organic material. This could be another distinctive trait although it does not necessary means that the opposite is true, too (i.e., that drywalls lighter in color are not defective).  So, this Chinese drywall test may not be conclusive by itself. However, associated with other types of testing for Chinese drywall, this test could be useful.

Additionally, if you experience any health problems at a high frequency or for the first time since living in the home with suspected defective Chinese drywall, this is another indication that you may be at risk.

Reference Cited
Rosen, G. 2009. Chinese Drywall Q & A Ver 3.0 Health Alert. 

Lab Testing for Chinese Drywall

Here is a guide to state-of-the-art laboratory testing that you may commission in order to test if your home or the home you intend to purchase has defective Chinese drywall.

Laboratory testing to identify defective Chinese drywall requires
  • Collecting and analyzing indoor air samples close to a wall or in rooms where the odor is felt most, over 1 or more days (in general, the fainter the odor the higher should be the collection time) and analyzing them for volatile organic compounds and main sulfur gases (including hydrogen sulfide, carbon disulfide, sulfur dioxide, and mercaptans); 
  • Collecting and analyzing a small sample of the suspected defective drywall itself and testing for sulfur, sulfates, sulfur compounds (both organic and inorganic) as well as the presence of pyrite in the drywall samples.
  • A large variety of metals (including Pb, Cd, As, Zn, Cr, Cu, Mn, Fe, Ca, Hg, Co, Ba) should also be tested in the drywall itself. 
  • Total organic matter should also be tested by the lab since defective Chinese drywalls were reported to have higher total organic content.