Greenboard drywall is a term used to describe moisture-resistant drywall. At its center, the same gypsum material is used in greenboard drywall. The difference lies in the surface materials, which have thicker paper as well as a wax coating to deter water. If you’re a homeowner that has frequent problems with wet drywall, you might look at greenboard as a lifesaver. However, you should know that greenboard drywall isn’t fully waterproof.
You can still have wet drywall problems with greenboard. Water can still get past the wax coating, and even the thicker paper sides can’t stop the water from reaching the center once that happens. It all depends on how much water the drywall came in contact with and for how long.
When not to Worry
Greenboard drywall is typically used in basements and other areas of the home where moisture and humidity are ever-present. If some water was splashed on the drywall, even if it has been a few hours since then, you don’t have to worry. The drywall will still need to be dried out, but mild amounts of water will not have significant long-term effects on the wall.
Much like normal drywall, you can use an absorbent sponge to remove the surface moisture. Then, fans and heaters should be used to dry out the drywall for at least 24 hours. Again, even after drying it out, a specialist should be called in to verify that the drywall is sound.
When to Worry
Remember, greenboard drywall is moisture-resistant, but that does not mean it is waterproof. If the drywall has come in contact with a lot of water for more than two days, the affected spot needs to be replaced. You might be wondering what the use of greenboard drywall might be if you have to be just as cautious with it as normal drywall, but the wax coating really does provide an extra protective layer. Without it, the water permeates through to the drywall’s core a lot faster.
If the greenboard is soft to the touch, it is damaged beyond repair. Once drywall has lost its strength, it cannot function as a proper wall anymore. If the wall has been wet for a while but it’s still solid, it can be saved.