Can Moldy Drywall Be Cleaned, or Must It Be Replaced?

Drywall is made of gypsum pressed between two layers of heavy paper. Both the paper and the gypsum soak up water, and mold spores settle into those layers quickly. Once mold takes hold, it spreads through the material, not just on the surface you can see.

A simple wipe with bleach or a cleaning product might remove the dark stains you can see, but it will not reach the mold growing inside the wall. Hidden mold can keep spreading and release spores into the air of your home. That is why most water damage pros recommend removing and replacing any drywall that has visible mold growth.

A water damage pro will start by checking how far the moisture traveled and how long the drywall stayed wet. They may use a moisture meter to test the wall. If the reading is high or the drywall is soft, they will cut out the affected section.

The pros will also look at the back side of the drywall if they can access it from behind. Mold often grows on the back paper where you cannot see it from the room. If they find mold there, cleaning the front does nothing, and the whole sheet needs to go.

Do not scrub moldy drywall yourself without protection. Mold spores can get into your lungs and cause irritation or breathing trouble. Wear gloves, goggles, and an N95 mask if you need to inspect the area. Open windows and turn off your HVAC system to keep spores from spreading through the house.

If you feel unwell after being near mold, see a doctor. For a large mold problem, leave the work to the pros who have the right equipment to contain and remove it safely. They can also identify the moisture source, like a leaky pipe or roof, so the mold does not come back.