Drywall After Water Damage

Whether drywall water damage can be patched or has to be cut out comes down to three things: what kind of water it was, how long the board stayed wet, and whether it has lost its strength. A small stain from a clean leak that was stopped and dried quickly can often be sealed and painted. Board that is soft, swollen, sagging or crumbling, or that sat wet for a long time, has to come out. In a warm, humid climate, the risk of mould tips more of those decisions toward replacing.

Stop the water first

No repair to drywall water damage lasts if the water is still coming in. Before anything is patched or cut out, the source has to be found and fixed.

Common sources in South Florida homes:

• A roof leak, often around flashing, vents or damaged tile
• A plumbing leak in a wall or ceiling, from a supply line, drain or fitting
• An AC condensate line or drain pan overflowing in the attic or a closet
• A water heater leaking in a closet or garage
• Wind-driven rain coming in around windows and doors during a storm
• Sweating ducts in the attic dripping onto the ceiling

A roofer or a plumber fixes the cause. The drywall comes after.

What kind of water it was

The source changes what can be saved.

Clean water. A leak from a supply pipe, a water heater, or rain coming through the roof is usually treated as clean, at least at first. Drywall soaked by clean water that is dried quickly can sometimes be saved.

Grey water. Water from a washing machine, dishwasher, or an AC drain carries more contamination. Drywall soaked by it is more often removed.

Flood and sewage water. Water that comes in from outside at ground level, or backs up from a drain or sewer, is treated as contaminated. Drywall it touches should be removed, along with the insulation behind it, well above the water line.

Clean water does not stay clean for long. Water that sits in a wall cavity picks up dirt and starts to grow bacteria and mould, so time matters for all three.

What can be patched

Drywall water damage can often be repaired in place when:

1. The water was clean, and the leak has been fixed.
2. The board dried out quickly and feels firm when pressed.
3. The paper face is intact, not bubbled, peeling or soft.
4. The board has not sagged, bowed or pulled off its fasteners.
5. There is no musty smell and no visible mould.
6. The area is small.

In that case, the repair is usually cosmetic. The stain is sealed with a stain-blocking primer, so it does not bleed through, and the area is painted. A small damaged section can be cut out and patched with a new piece, taped, finished and painted to blend in.

What has to come out

Drywall should be cut out and replaced when:

• It is soft or crumbles when pressed
• The paper face has bubbled, peeled or separated
• A ceiling is sagging or bulging, which can mean water is sitting on it
• Joint tape has lifted or the seams have split
• It was soaked by grey water, flood water or sewage
• It stayed wet for long enough that mould is likely
• There is mould on the surface or a musty smell from the wall

When a section comes out, it is cut back to dry, sound board, and the cavity behind it is checked. Wet insulation is usually removed too, because it holds water against the framing for a long time. The framing is dried before new board goes up. On walls, damaged baseboards often come off as well.

A sagging ceiling is a safety matter. If a ceiling is bulging with water, keep everyone out from under it and turn off any lights or fans in that area at the breaker. Do not poke it.

The mould question

Mould needs moisture, warmth and something to feed on. Drywall paper is good food, a wall cavity is dark and still, and South Florida supplies the warmth and humidity. Wet drywall in this climate can start to grow mould quickly, and it often starts on the back of the board where you cannot see it.

That is why drying fast matters so much:

• Run the air conditioning to pull moisture out of the indoor air
• Use fans to move air across the wet surface
• Use a dehumidifier if you have one
• Open cabinet doors and move furniture away from wet walls
• Take wet items out of closets

A pro can check the wall with a moisture meter, which shows whether the board and the framing behind it have dried out, rather than relying on how the surface feels. A board that looks dry on the face can still be wet inside.

If mould is visible, or the area smells musty, the drywall around it should come out. Florida licenses mould assessors and mould remediators. For more than a small patch, those are the people to call, and your insurer may ask for their report. Do not paint over mould; it will come back through.

The order things usually happen in

When a wall or ceiling has drywall water damage, the work usually runs like this:

1. Stop the water and make the area safe.
2. Photograph the damage, the source and anything that was soaked, with the date.
3. Call your insurer if the damage is large or the cause might be covered.
4. Have the source repaired by the right trade, such as a plumber or a roofer.
5. Dry the area and check it with a moisture meter.
6. Remove damaged drywall and insulation, and deal with any mould.
7. Hang new drywall, tape, finish, prime and paint.

Skipping ahead is the most common mistake. New drywall over a wet cavity, or paint over a damp stain, tends to stain again, crack, or hide mould until it spreads.

Electrical outlets and switches in wet walls

If water has reached outlets, switches or light fittings, turn off the circuit at the breaker and leave it off. Have a licensed electrician check the wiring and devices before the power goes back on. That part is not drywall work.

Who does what

Drywall patching, cutting out damaged board, hanging new board, finishing and painting are handyman work. The leak itself goes to the licensed trade it belongs to: a plumber, roofer or AC contractor. Mould beyond a small area goes to a licensed mould remediator, and wiring goes to an electrician.

How One Call fits in

One Call Home Pros is a connector. Tell us where the water came from and what the drywall water damage looks like now, and One Call arranges the right people in the right order: a licensed plumber or roofer for the cause, and a vetted, insured handyman for the drywall. The pros do the work. One Call vets them, arranges the visits and stays with the job. You pay One Call, and One Call pays the pro.

Get the wall put right

If a leak has left a stain, a soft patch or a sagging ceiling, the first job is the source, then the drywall. Tell One Call what happened, and we connect you with the right vetted local pros.