What is Corrosive drywall?

Corrosive drywall is the indoor air quality industry slang for problem drywall. The Consumer Product Safety Commission on behalf of the US-EPA identified problem drywall to be corrosive in nature, effecting primarily copper which leads to deterioration of items such as refrigerators, HVAC evaporator coils, and wiring. This defective building material was utilized in the US between 2001 – 2008.

How do I identify Corrosive drywall?

Not all Corrosive drywall is of Chinese origin, but much was manufactured in China so the identification of problem drywall is not as simple as looking for the “Made in China” marking. On August 27, 2010, the Consumer Product Safety Commission in conjunction with the Department of Housing and Urban Development released “Interim Guidance- Identification of Homes with Corrosion from Problem Drywall” which presented an identification method for problem drywall. This method involves two steps:

Step One: A Threshold Inspection
This step requires the documentation of the blackening of copper wiring and/or air conditioner coils and documentation that the drywall was install between the years of 2001 and 2008.

Step Two: Corroborating Evidence
This step involves the scientific gathering of data which would support the evidence gathered during the Threshold Inspection. The criteria for this step ensures that corrosion related to other house hold conditions is not falsely linked to drywall. For installations between 2001 – 2004, at least four of the corroborating conditions must be met. At least two of these conditions are required for identification of problem drywall in installations performed between 2005 – 2008.

1) Corrosive condition exhibited by the corrosion of copper coupon placed inside the home. Documentation of the production of copper sulfide in the corrosion is required. (Assured Bio DIY Corrosive Drywall Test Kit)
2) Markings on the drywall indicating that it was made in China.
3) Elemental Sulfur levels exceeding 10ppm within the drywall of the home. (Assured Bio Elemental Sulfur Analysis)
4) Elevated levels of hydrogen sulfide, carbonyl sulfide, and/or carbon disulfide emission exhibited in an ASTM chamber.
5) Corrosion of copper forming copper sulfide in controlled laboratory conditions. (Assured Bio Corrosion Test)

Assured Bio Testing Options

FT-IR (Fourier Transform Infrared Spectroscopy)

Assured Bio teamed with researchers from the University of Tennessee to select and develop a rapid, cost-effective test to provide general overview for a potential problem. This highly sensitive method of analysis is used in crime labs and courtrooms across the country for everything from detecting illicit drugs to counterfeit money. It is ideal for rapid property screening.

The above graph is a sample of the comparison data used to identify problem drywall. The red line is the spectrum for known Corrosive drywall samples and the blue line is the spectrum for American drywall samples.


  • Cost Effective – $159/analysis
  • Direct Detection – Detects actual contaminants, not gases
  • Rapid Turnaround – Results within 24 hours
  • Easy-to-understand Report – Definitive and simple result
  • Customer Service – Free phone consultation on results
  • Accredited Laboratory – a lab and results you can trust

Corrosion Testing

The scientists at Assured Bio have validated and offer two Corrosion Test methods, both meet the criteria for establishing corroborating evidence as outlined by the Consumer Product Safety Commission. One option is a Do-It-Yourself Corrosion Test. This method allows the home owner the ability to test multiple areas of concern in the home over a period of 30 days. The second is Corrosion Testing performed in a controlled laboratory chamber with a more rapid turnaround time of 7 days.


  • Price – Only $150/per Analysis
  • Report – Easy to read report that includes pictures of your copper coupon
  • CPSC Recommended – Method meets the corroborating evidence criteria
  • Customer Service – Free phone consultation on results
  • Accredited Laboratory – A lab with results you can trust

Elemental Sulfur Testing

Clients looking for a true empirical comparison of their drywall to materials known to cause corrosion often prefer the Elemental Sulfur method. This quantitative analysis utilizes Gas Chromatography/Electron Capture Detection (GC/ECD), reporting S8 in parts per million. Results may be directly compared to the 10ppm standard as identified by the Consumer Product Safety Commission. 10-14 day turnaround.


  • Price – Only $159/per Analysis
  • Report – Easy to read and contains the actual ppm of strontium sulfide in your sample
  • CPSC Recommended – Method meets the corroborating evidence criteria
  • Customer Service – Free phone consultation on results
  • Accredited Laboratory – A lab with results you can trust

    Order The Corrosive Drywall Test Kit

Test Instructions:

Step 1– Remove copper coupons from plastic bags and place them in 10 different locations around the building/structure you are testing. Be sure to not throw the plastic bags away. Do not apply tape or any substance to the coupons.

Step 2– Wait 30 days. Make sure that the copper coupons are not disturbed/damaged.

Step 3– After 30 days, collect the copper coupons with gloved hands and place each one individually back in the plastic bags they came in.

Step 4– Send the coupons back to our lab and wait for your results!

Interim Guidance – Identification of homes with corrosion from problem drywall
Remediation Guidance for homes with corrosion from problem drywall