Signs of water in a ceiling or wall
- Yellow or brown stains, often with a darker ring
- Paint that bubbles, peels or flakes
- Drywall that feels soft or crumbles when pressed
- A ceiling that sags or bulges
- Baseboards pulling away or swelling
- A musty smell with no visible cause
- Drywall seams or nail heads showing through
Can water hide behind walls?
Yes. Water follows framing, pipes and wiring, and it collects at the bottom of wall cavities where insulation holds it in place. The painted surface can look normal for days. Musty odor, peeling paint and swollen baseboards are often the first outward signs.
Where the water usually comes from
| Where the damage shows | Likely source |
|---|---|
| Ceiling below a bathroom | Toilet seal, tub or shower drain, supply line |
| Ceiling on the top floor | Roof leak, ice dam, attic condensation |
| Ceiling below a kitchen or laundry | Dishwasher, sink drain, washing machine hose |
| Wall near a window | Failed flashing or caulk |
| Exterior wall in winter | Frozen pipe or ice dam |
| Bottom of a basement wall | Seepage or a flood on the floor |
A sagging ceiling is a hazard
Drywall holding water gets heavy and weak. A bulge means water is pooled above it. Keep people out from under it and move furniture if you can do so safely. Do not push on it. We release the water in a controlled way and take down drywall that has lost its strength.
How the work is done
- Find and stop the source. If it is plumbing, shut off the water. If it is the roof, see ice dam and roof leak water damage.
- Measure. Moisture readings show how far the wet area extends past the visible stain.
- Open what is necessary. Wet insulation is removed. Drywall that is firm is kept.
- Dry the cavity with directed air and dehumidification. See structural drying.
- Confirm dry before the wall or ceiling is closed and repainted.
Can water-damaged drywall be saved?
Often it can, if the water was clean, the board is still firm and drying starts quickly. Replace it when it has sagged, softened, grown mold or was wet with contaminated water. Painting over a stain without drying the cavity traps moisture and the stain returns.
Plaster in older homes
Many older houses near downtown Anoka have plaster over wood lath instead of drywall. Plaster tolerates water better than drywall and dries well, but the wood lath behind it swells and can push the plaster loose. Wet plaster ceilings are checked for separation before anyone decides to keep them.