From a visual standpoint, mold is ugly because it discolors drywall. The big question is whether you can simply paint over it. Or, do you have to replace the drywall?
What’s So Bad About A Little Mold?
Several problems show up with moldy drywall. The first concern is the mold will grow back. The underlying problem has not been removed or solved yet. It means that even if you do replace the mold-riddled wall board, more mold will probably grow in its place.
The background problem could range from a leaking roof to bad plumbing, to simply too little ventilation say in a bathroom. Whatever the reason there is mold, it could be a very serious underlying problem or present a quick fix. Figure out and fix whatever is causing the mold before you replace anything.
The another reason mold is a flag because of the health issues it causes. While many people do not have any outward reaction to mold, a big portion of people are allergic to mold. They may cough, sneeze, and feel like their ears and nose are always stuffed up. Feeling sick all the time costs people time, and money spent taking days off from work and tending to sick kids.
More than that, some types of mold are deadly. They cause cancer and neurological disorders. So, if you have been feeling foggy ever since moving into your home with the mold in the walls, then you may want to replace the drywall.
Rule Of Thumb
Assuming you have identified the type of mold and found all of it, here are some rules of when/what to replace. Wherever there is mold, use the 6-inch rule. Its guidance states that you should cut out that far above where the mold occurred.
When looking at the dry wall, it may run deep. Be sure to check the back of the dry wall for signs of mold too. Though, to be on the safe side, and if you want to start clean, replace the full swaths of drywall.
While most people turn to water and bleach solution to clean mold, vinegar may be a more suitable option. Sure, for non-porous surfaces bleach cuts through and eliminates almost any germ, bacteria, and mold.
For something more porous, bleach may not cut it. Its limitation is that it will cut through as effectively as vinegar. Though, even still, the issue is that moisture will be sitting inside the drywall, especially if it is unpainted. That means you guessed it — replace unpainted drywall.
When you are replacing a section of drywall, ensure there are two beams behind the drywall. Measure the dimensions of the segment of drywall you removed. Cut out a new piece of the same size and fit it into place into the beams. Apply drywall compound and let it dry for one day. Sand the compound and then you are ready to paint it.