How to Know If Drywall Is Bad

Find out when the drywall was installed. According to the CPSC, the drywall must have been installed between 2001 and 2009 for it to have been from the batches of bad drywall imported from China.

Check for corrosion. The chemical emissions from bad drywall will cause corrosion in metal and copper fixtures throughout your home. Look at your home's copper pipes, plumbing and any uninsulated electrical wires. Copper wires will appear black. If you have an air conditioner, determine if it's in working condition. The corrosion could affect the air conditioner's evaporator coils.

Notice any sulfur odors, which can smell like rotten eggs, fireworks or matches. CBS News interviewed a family in 2009 whose home smelled so bad due to bad drywall that they were forced to leave.

Look for a "Made in China" label. If you can access the back of the drywall, check for a stamp that states the material was manufactured in China. However, the Centers for Disease Control and Prevention, in its restatement of the CPSC guidelines, emphasized that not all drywall made in China will bear that label or have obvious markings that identify its source.

Contact a professional assessor to do lab testing. The CPSC recommends testing if the drywall was both installed during the appropriate time period and if copper erosion is evident. Drywall installed between 2005 and 2009 must have at least two of the five factors, which include "Made in China" markings. The other factors include elemental sulfur in the drywall, copper sulfide on grounding wires, sulfide gas emissions from the drywall and corrosion caused by the drywall under test conditions. Drywall installed between 2001 and 2004 must have four of these factors to meet the test of bad drywall.