Forensics Expert Discusses Chinese Drywall

Lake Forest, CA"Regardless of what people say about US building developers and contractors, for the most part they didn't buy Chinese drywall to save money but ordered it simply for supply and demand," says Doug Derry, field services manager, CBI Forensics. And there was a lot of demand after Hurricanes Katrina and Wilma. "Shipping records show that since 2006, 550 million pounds of drywall were imported from China into the US—enough for about 100,000 homes."

Derry says forensics inspectors started to investigate allegedly toxic drywall in December 2008. Based on what they saw, Knauf Plasterboard Tianjin LTD., which is a subsidiary of German-based Knauf, supplies upwards of 50 countries with drywall and insulation. America ran out of drywall during the building boom, so between 2004 and 2007 Chinese drywall was being used to build American homes. (On March 24, 2009 Florida's Atttorney General launched a criminal investigation into Knauf and L&W Supply Corp, to investigate whether the companies committed any deceptive sales or marketing practices.)

"Interestingly, you can hear so much about building companies such as Lennar but more often than not, they trust their drywall contractor to supply, install and tape the houses," explains Derry. "All they know is that they order their subcontractors to begin delivering the drywall in preparation for installation. Perhaps during this period of time this Chinese drywall was available quickly and in the sizes and thicknesses required for the job."

So all this drywall is getting installed and it wasn't long before Florida homeowners found that drywall was affecting their air conditioning; their coils were turning black within a year. Derry says this was occurring in certain subdivisions, along with rotten egg/sulfur smells. "Once these homes were investigated, it was associated with drywall that was stamped 'China' or 'Knauf' and people started putting 2 and 2 together," says Derry.

"By 2006, Knauf hired experts to investigate the homeowner's complaints," Derry says. "Knauf apparently found no health concerns related to any emissions they tested in residents' homes. But private investigators hired by residents found something going on with copper wiring, copper plumbing and even copper coins turning black. It was only in houses with Chinese drywall. Something was causing the copper to turn black, like a black soot.

"Upon further testing, investigators found 3 types of sulphide gasses: carbon disulfide, carbonyl sulfide and dimethyl sulfide. Hydrogen sulfide (which has the characteristics of the rotten egg smell) was only found in some testings. I also talked to investigators who were hired by Lennar: they tested each house, and recorded amounts of chemicals found in each room. It was rather like luck of the draw: some houses were found with the gasses listed above and some had higher readings: it almost corresponded with the amounts of moisture found in those homes investigated. Now it has been found in a number of other states such as Louisiana and Mississippi."

Although Chinese drywall is cause for concern, Derry says the problem has ignited a lot of fear in homeowners who purchased homes built post-Katrina/Wilma, i.e., 2004. And they are keeping investigators busy. Homeowners have read online about potential health problems such as respiratory problems, breathing difficulty and nose bleeds. "Homeowners read these bulletins and reports from consumer watchdogs and many have respiratory or sinus problems. They start to wonder if their house is contaminated with the drywall," he says.

The Chain of Command

Who is responsible—Knauf? Lennar? Derry says his company also found US investment groups had purchased drywall, had it shipped to the US from China, and then sold it to different supply houses.

So we have this long chain of command stretching from the manufacturer to the homeowner. Apparently, the manufacturer mined gypsum and made the drywall with fly ash—a waste material found in power plants. Since that time, a new mine has been used to manufacture drywall. " I don't know if their product is still being shipped to the US. I know some politicians are trying to ban any drywall coming from China," says Derry.

Advice to Homeowners

Derry suggests homeowners first contact their builder if they suspect their home is built with Chinese drywall. If they can't help, there are a few simple steps you can take:

If you are handy enough to look for yourself, outside of the rotten egg smell, get into the attic and push some insulation around to expose the backside of the drywall. Look for a stamp (China or Knauf). Look for copper turning black; appliances and equipment failing prematurely, even TV's and cable boxes and personal jewelry turning black. Remove a switch plate cover off a light switch, get a flashlight and look at the site of the light switch to see if the copper wire is blackened—don't touch it though!

Derry also warns homeowners to check inspector's credentials. A lot of people have taken an interest in this and a lot of unqualified inspectors can do a "Chinese Drywall Inspection." Some states require that inspectors join organizations and have certification—across the country you can check out and find inspectors at www.icc.org or www.nachi.org (National Association of Certified Home Inspectors).

"One company is already cashing in and selling a Chinese drywall inspection kit," says Derry. "It is made to test water samples for sulfur levels—to determine if water is drinkable. I talked to the manufacturer and he said it would not work on drywall." Good to know…