Wet drywall can often be dried in place if the water was clean, the board is still firm, and drying starts within a day or two. It should be replaced if it is soft, sagging, crumbling, stained deeply, moldy, or was soaked by sewage or dirty water. Wet insulation behind it usually has to come out too. Not sure which yours is? Call (413) 603-1274.
Dry it or replace it
| Usually dry in place | Usually replace |
|---|---|
| Clean water from a supply pipe | Sewage or floodwater |
| Firm when pressed | Soft, swollen or crumbling |
| Caught within a day or two | Wet for several days |
| No mold visible | Mold on either side |
| Walls | Sagging ceilings |
Ceilings are different
Wet drywall on a ceiling sags under its own weight and the weight of the water. A sagging ceiling should come down in a controlled way. Do not stand under it. See ceiling water damage repair.
What is behind it matters
Fiberglass insulation soaked in a wall cavity often has to be removed so the cavity can dry. The back of the drywall is where mold starts first, out of sight. See how to check for mold after a leak.
Old Chicopee homes
If your walls are plaster rather than drywall, the rules change: plaster often can be dried in place, but takes longer. See why plaster takes longer to dry.
Drywall types
Standard drywall has a paper face on both sides, which is what mold feeds on when it stays wet. Moisture-resistant drywall, often green or blue, holds up better but is not waterproof. Paperless drywall with a fiberglass face resists mold better. Cement board, used behind tile, handles water well. If wet drywall in a basement or bathroom must be replaced, ask whether a more water-resistant type makes sense for that spot.
Cutting it out cleanly
When drywall has to come out, a straight cut a little above the wet line is easier to patch than ragged pieces. Removing the bottom of the wall also lets wet insulation come out and the cavity dry. The cut line should be based on moisture readings, not just the visible stain, since water wicks up past what you can see.
When it can stay
Drywall that is still firm, had only clean water, and is drying within a day or two often stays. Readings decide, not looks.
Water from above vs water from below
Drywall wet from a leak above, such as a burst pipe on the next floor, often has a wet top edge or a ceiling stain, and the water may run down inside the wall. Drywall wet from water on the floor wicks it upward from the bottom. Wicking can reach a foot or more above the water line. Both need readings across the full height of the wall, not just where the stain is, before deciding what to cut out.
Bathrooms
Drywall behind tile in a shower that has leaked for a long time is often soft and moldy, even when the tile looks fine. That usually means removing the tile, the board behind it and rebuilding with a proper backer.
Questions
How long can drywall stay wet before it is ruined?
Mold can start within 24 to 48 hours. After that, replacement becomes more likely.
Can I just cut out the stained part?
Cut back to where readings show dry, usually a bit past the stain. See drywall and plaster repair.
Wet drywall? Call now
Call (413) 603-1274 now. Locally owned in Chicopee.