subject: Chinese Drywall Cpsc Remediation Guidance [print this page] Yesterday, the CPSC released initial guidance for the remediation of homes affected by Chinese drywall.
Their guidance largely reflects what we released on our website over a month ago.
There is no easy way to repair Chinese drywall. The process involves removing the defective material as well as any of the building materials that could be affected by the hydrogen sulfide.
The first step is selective demolition. Carefully removing cabinets, counter tops, sinks, toilets, and other solid surface materials will allow them to be reused when the home is rebuilt. Some hard surface materials cannot be reliably removed without being destroyed. For example, tile floors cannot typically be removed in such a manner that they could be reused. The materials should be stored off site so that they can be protected from being damaged. Only materials that are not porous can be reused.
The bulk of the demolition work can now begin. This will involve tearing out and removing all of the drywall. This will remove the cause of the contamination. Next, any material that could be affected by the corrosive nature of hydrogen sulfide should be removed. This includes all electrical components - wiring, breakers, panels, etc. In addition, smoke alarms and HVAC should be removed. The metals in these components are likely to be highly corroded in a home that has contained Chinese drywall. In the case of electrical components, this corrosion can cause high levels of heat as current passes through the compromised conductor, possible leading to house fires.
At this point, we recommend the property be cleaned with high efficiency vacuums and a pressure washer or manual wipe down of the structure's surfaces. This process will remove the drywall dust that results from the demolition.
The CPSC specifically did not address - and did not even study - the possibility of cross contamination amongst framing members, concrete block, etc. We have numerous ground truth reports of home that have been stripped of defective drywall that maintain the odor and caustic characteristics of Chinese drywall. While we do not feel that the framing will off gas at the level produced by the drywall material, it is likely that trace levels of hydrogen sulfide will be released by structural members, especially wood framing members. Wood is an extremely porous material and acts like a sponge - soaking up the gases that have been released. The CPSC advises home owners to consider that the home may need to be ventilated to allow for the hydrogen sulfide gas that has been absorbed. We feel that a natural diffusion period would suffice. There is no evidence currently to support the application of oxidizers, etc. The unknown, however, is the length of time necessary for the diffusion to occur. To encourage the natural process of diffusion, the property can be heated and placed in a low-grade vacuum with specially designed fans.
Prior to rebuilding the home, the property should be cleared of cross contamination by an insurable protocol that guarantees the home free of defective drywall. After the home has been cleared, the process of rebuilding the home can begin. This clearance will render the property as "certified remediated."
Home owners and home buyers should be cognizant of the process that is necessary to properly remediate a home that contains Chinese drywall. Simply replacing the drywall is not sufficient.
