While much to do has been made of the potential health problems associated with exposure to Chinese drywall, experts have begun looking into the issues caused by the use of these materials. Gary Rosen, Ph.D., has tendered a study on Chinese drywall that exposes the structural side of these building materials and certain items are worth noting. His Q&A regarding Chinese drywall answers several questions about the wallboard and exposes problems that might not be immediately considered.
First, the identification of Chinese drywall can help home or property owners in their pursuit of answers. According to Rosen, “All US drywall has special markings on the edge tape. If there is no writing on the edge tape indicating an American brand, or the edge tape is generic looking either clear/milky plastic, or plain white paper this would rule out American drywall.” As such, because of the specific labeling of U.S. drywall, that wallboard that stands out as without these elements should be looked into further. One brand of problematic drywall, Knauf brand, has the name ‘KNAUF’ stamped on the back. It is important to note, however, that NOT all Chinese drywall is considered problematic but, rather, has been ISO approved, such as the BNBM drywall from Beijing.
Because of the variance that has been found in the test results of drywall considered problematic, Rosen avoids declaring Chinese wallboard a public health hazard just yet but focuses, instead, on the danger and dilemma created by the use of the material in construction. While he remains inconclusive on just how damaging the drywall may be to electrical fixtures and metal elements, Rosen, on the topic of replacing ‘good,’ non-harmful drywall used around the Chinese drywall, does state “no doubt removal of the drywall and replacement with new is the best approach.”
Again, avoiding the potential health issues associated, the author directly approaches the structural problems created by Chinese drywall:
Q. Does the Chinese drywall weaken over time as some people claim?
A. The reactions that cause the release of the sulfur gases also appear to be weakening the Chinese drywall.
We believe that the Chinese drywall has problems not only in regard to giving off sulfur gas (pollution) but, as a result of this weakening, it also has structural problems: Does not meet accepted standards of quality for building materials (construction defects.)
It is known that problem Chinese drywall has a significant amount of pyrite (with is composed of iron and sulfur). And it has been known throughout the centuries that stone/rock used for building must be free of pyrite because in weathering, pyrite deteriorates and would release corrosive iron sulfates that discolor and destroy stone. The same appears to be true for [drywall].
We believe that due to its continually weakening state, Chinese drywall material on ceilings will eventually collapse. Testing is underway to quantify the extent that Chinese drywall is weakening.
For more information from Gary Rosen, Ph.D., regarding Chinese drywall or mold issues at large, visit his website at www.mold-free.org.