corrosive drywall impacting Hvac coils and pipes VacavilleHalloween is around the corner, and here in Vacaville, a lot of us show off our spooky disguises at the annual Halloween Stroll downtown. But did you know that your walls might be disguising something too? It’s not a ghost or a goblin—it’s corrosive drywall.

If you’ve noticed that your electrical fixtures or in-wall piping are corroding, you might have defective, and dangerous, drywall. In 2009, a case was brought against mostly Chinese manufacturers of drywall after a study done by Environmental Health & Engineering Inc. found that the imported drywall was releasing dangerous gasses into homes.

Many of the cases involved homes that were damaged in Hurricane Katrina, but the drywall was also shipped to over 42 states around the country, including California. If you’ve purchased and installed drywall within the last decade, here’s what you need to know so the only scary thing you come home to is your kids digging into their candy stash.

How to Identify Dangerous Drywall

Chinese drywall, or odorous wallboard, imported between 2001 and 2009, has been found to give off gasses of volatile chemicals, including hydrogen sulfide. The reason is the improper manufacturing of the fly ash in the drywall.

Most drywall has fly ash, but in the Chinese drywall, it degrades easily in warm and moist areas. This means drywall in bathrooms, and the walls surrounding your HVAC unit, could begin to break down and give off smelly sulfur gas. This is bad news for the health of your home,your plumbing, and your HVAC appliances. Common ways to identify odorous wallboard are:

  • Rotten egg smell in your home: If your home smells like rotten eggs, it could be odorous wallboard. This smell is often strongest upon entering the home, and goes away after you have been in your home awhile.
  • Labeled as “Made in China,” “China,” or “Knauf”: If your drywall has one of these labels on the back, it is considered dangerous. Just be aware that not all defective wallboard is labeled, so be sure to look out for the other signs if you can’t find a label.
  • Rusted cooling coils: The cooling coils inside your AC unit may start to rust if the sulfur gas in your drywall is released into your home. Sometimes rusty coils are mistaken for a refrigerant leak, so make sure that your HVAC professional takes a thorough look at them. A closer look might reveal black sooty deposits, a sure sign that corrosive gas is present.

How Dangerous Are These Gases?

Sulfur off-gassing can cause health problems and damage to your home within a short period of time. Some common dangers of sulfur gas in your home are:

  • Respiratory issues: Within a few hours, the presence of sulfur gas in your home can cause eye irritation, coughing, nausea, and chest pain. Prolonged exposure may also cause more severe respiratory issues.
  • HVAC coil corrosion: This is often one of the first signs of the presence of sulfur gas. Sulfur gas can quickly begin to corrode the coils in your HVAC unit, lowering the efficiency of your unit by reducing the coils’ ability to reject heat. If left alone, it can even cause the unit to fail.
  • Plumbing corrosion: Just like the coils in your unit, plumbing piping in walls and bathrooms can corrode because of exposure to sulfur gas. Prolonged exposure can weaken pipes and eventually cause leaks. Rust that leaches into water can also contaminate drinking water.
  • Electrical corrosion: The metal components and wiring of the light fixtures in your home can also experience corrosion from sulfur gases. These can cause lights to fail and receptacles to malfunction, potentially becoming a fire hazard.

What to Do About Dangerous Drywall

If you suspect that your home’s drywall is emitting sulfur gas, report it to the U.S. Consumer Product Safety Commission so it can be investigated. You may be eligible to receive a percentage of the settlement from litigation if your drywall is part of the defective imported inventory.

Your insurance should also offer coverage if an inspection proves your drywall to be harmful and dangerous to your health. But don’t forget to also have HVAC coils, piping, and electrical devices inspected for corrosion as well—they will likely need to be repaired or replaced along with the drywall. An HVAC professional can sometimes recommend coating the coils to prevent further corrosion before replacement is required. They may also recommend annual coil cleanings for cases such as this where coils may be more susceptible to other corrosive agents.

This is a spooky time of year, but don’t let hazardous drywall scare you. If you suspect you might have defective drywall, make sure to contact the U.S. Consumer Product Safety Commission and your insurance company so you can have it inspected as soon as possible. If you find that sulfur gases have corroded your HVAC and piping, contact a trusted HVAC professional to talk about replacing damaged appliances and parts—the sooner you find out whether or not you have Chinese drywall, the better you’ll feel, and the safer your home will be.

If you suspect you have damaged piping or coils in your walls, contact Bell Brothers today, your local and trusted HVAC professionals for over 25 years.