What Happens to Drywall When It Gets Wet?

Drywall is made of a gypsum core sandwiched between two layers of heavy paper. The paper is the first to soak up moisture, and once wet, it loses strength quickly. The gypsum core is porous, so it absorbs water like a sponge, swelling and softening as it does.

If the water is clean and the drywall dries within a day or two, it might survive with just some staining or minor warping. But if it stays wet longer, the core can break down, and the paper can separate. The longer the exposure, the more likely you'll need to replace it.

If the drywall got wet from clean water and you caught it within 24 to 48 hours, drying might be enough. Use fans and dehumidifiers to pull moisture out. However, if the water came from a sewer or flood, replacement is safer because contaminants can linger.

For small areas, you can cut out the damaged section and patch it with new drywall. But if the water reached the insulation or framing behind the drywall, those materials may also need removal. The pros can assess the extent of damage and tell you what needs to go.

If the water damage is extensive, covers a large area, or came from contaminated sources, professional help is wise. The pros have industrial-grade drying equipment and moisture meters to detect hidden water in walls and ceilings. They can also remove wet insulation and drywall safely.

You might also need professional help if you see mold growth or if the drywall is on the ceiling, where sagging can be dangerous. A water damage inspection can reveal the true extent of the problem. Wet winters in many regions make this a common issue, so don't delay.

• Large areas of wet drywall, over several square feet
• Water from sewage, flooding, or chemical spills
• Signs of mold growth on or behind the drywall
• Ceiling drywall that is sagging or cracking
• Persistent musty smell after drying efforts
• Unknown source of water that keeps coming back