What is Chinese drywall?
Chinese drywall refers to defective drywall imported from China. This drywall was used to build over 100,000 homes in 20 different states. Chinese drywall is contaminated with strontium sulfide which is a harmful compound found in coal-fired power plants. In hot and humid environments, strontium sulfide off-gases into hydrogen sulfide, carbon disulfide, and carbonyl sulfide. These sulfide gases can impact the health of the people living in the home and corrode metals.
Why is it hazardous?
The biggest reason why Chinese drywall is considered hazardous is because it can impact the health of the people living in the home. The sulfide gases emitted from Chinese drywall can cause a variety of symptoms including headaches and nose bleeds. According to the Center for Disease Control and Prevention, the respiratory tract and the nervous systems are the most sensitive to hydrogen sulfide exposure. The most frequently reported symptoms are:
• irritated and itchy eyes and skin
• heavy and hard breathing
• recurring cough
• runny nose
• nose bleeds
• strong headaches
• sore throats
• sinus infections
• asthma attacks
Chinese drywall can also cause corrosion and blackening of metals in the home including the electrical wiring and air conditioning evaporator coils.
According to studies by the Consumer Product Safety Commission, blackening of electrical wiring does not result in a reduction in the ability for the wire to carry its rated current. In their studies, the CPSC did not observe any hazards pertaining to electrical wiring and Chinese drywall. They still recommend the removal and replacement of electrical distribution components when remediating the home, including receptacles, switches, and circuit breakers.
What are the signs of Chinese Drywall?
One way to determine if a house has Chinese drywall is by looking at the electrical wiring and A/C evaporator coils. Blackened electrical wiring and A/C evaporator coils are a common sign of Chinese drywall.
Homeowner’s can also look for Chinese markings printed on the drywall although not all drywall imported from China is problematic. Lab tests have to be performed to confirm if drywall imported from China is problematic or not.
During a home inspection, home inspectors look for visual signs of Chinese drywall while inspecting the electrical and air conditioning systems. The pictures below were taken during a home inspection in Tampa, FL.
How can you remediate it?
Chinese drywall has to be remediated by a contractor that is experienced with Chinese drywall. The CPSC has specific guidelines for remediation. If the remediation is not done properly, sulfide gases will continue to be a problem for the people living in the home. Proper remediation requires the removal of all the problem drywall including the drywall dust.
The average cost to properly remediate a house with Chinese drywall is between $60-80 per square foot. In some cases, the cost to remediate a house can be as much as the cost of the house itself.