Water can be destructive. When it meets the drywall that makes up your interior walls and ceilings it can make them look unsightly — or worse, it can damage wallboard enough that it collapses and falls apart, which can cause huge homeowner headaches. Don’t panic though. You can repair walls and ceilings that have water damage as long as you have the right know-how and tools to get the needed repairs done. Learn how to do it yourself with this step-by-step repair guide.
Step 1: Find the Water Leak
Sometimes it will be obvious that you have water leaking either behind your walls or onto the ceiling from above. The ceiling or walls may show visible signs of moisture, dripping water, or signs of failing structural integrity. Ceiling drywall panels may sag or crumble under the weight of water that saturates the naturally porous gypsum material. Other times, you may notice small signs like coffee-colored stains that may expand over time.
Before making any repairs, you need to find the source of the water leak. This can be frustrating, but if you don’t fix the source of the water problem first, repairs will do you no good. Whether it’s a leaky roof, a broken pipe or leaking toilet, it can sometimes be difficult to locate the source. Water can travel far from the leak and cause damage somewhere you wouldn’t expect it. This means you have to do some exploration and investigation. Remove damaged drywall so that you can better see where the leak is coming from (see Step 2) and so you can dry out the water-damaged space.
Depending on how long the leak has gone unchecked, there may be mold present in or on the drywall. Some mold, such as “black mold”, is better off remediated by professionals because it may be very toxic when present in large amounts. If you do have large amounts throughout an interior area — anywhere around 10 sq. ft. — call a professional to have it removed.
If only a small amount of mold is present, you can safely remove the mold or the moldy drywall yourself, if you take precautions. Wear gloves, safety goggles and a dust mask so that you don’t breathe in the mold.
In some serious cases where there is severe water damage, you may need to call in a professional contractor to repair the source of the leak or to repair the damaged walls or ceiling.
Step 2: Remove Water-Damaged Drywall
Before starting, put down drop cloths or tarps to catch all the drywall pieces, dust and debris created by removing the damaged drywall. This will make cleanup easier and protect surfaces from the dust and mess.
Check the drywall to see how much damage has been done. Heavily water-infiltrated wallboard will sag from ceilings or crumble to the touch. Remove all compromised drywall by hand or use the claw end of a hammer or a wrecking bar to remove it. If drywall panels only show water stains but aren’t structurally compromised, they may be repairable by cutting out the damaged portion. When cutting out around the damaged area, use a keyhole saw to cut the hole into a square or rectangular shape. You can then make a patch with another piece of drywall for the repair.
When tearing out the compromised drywall, wear safety goggles and a dust mask for protection.
Step 3: Make Repairs
If you are patching the wall or ceiling, measure the square or rectangular area of the wall that you cut out from Step 2. Use these dimensions to cut a replacement piece of drywall to fit, 2" longer and 2" wider than the hole. Lay the replacement piece of drywall on a flat surface with the backside facing up. Measure in 1'' from all four edges and draw a line using a pencil. This should form a shape the size of the hole. Using a straight edge and utility knife, cut through the backside paper and the drywall gypsum, but not the front-facing layer of paper. Using a putty knife, peel away only the backside paper and gypsum layer. Be careful not to tear the front-facing paper.
If the patch isn't a perfect fit, place it against the hole and trim to size with a utility knife.
Holes bigger than 6", up to 12'', require a slightly different process because the patch needs more support. Using a drill, create two small holes through the piece of replacement board. Feed a piece of string through and tie both ends to the middle of a stick. Allow for about 8" of string between the board and the stick. The "stick side" of the board will be the front. The stick will be used to hold the patch in place. Twist the stick to apply pressure to the rear of the board. This will steady it in the hole. Apply a smooth coat of cement adhesive around the edges. Insert the patch into the hole and position it so the cement adhesive firmly grips the solid area around the rear of the hole. Turn the stick clockwise, twisting the string and increasing pressure against the patch board at the rear of the hole. This will hold the board firmly in place until the cement adhesive dries.
To make it easier to insert the wallboard material through the hole, be sure to hold it at an angle.
If you're working with a smaller hole (up to 6"), apply a thin layer of joint compound around the hole. Place your patch into the hole. Using a putty knife, work the paper edge down into the compound. Feather the edges of the compound and allow it to dry. Sand lightly with a fine-grit sandpaper and apply a second layer of joint compound to finish the repair.
For larger holes (between 6" and 12"), allow the cement adhesive to thoroughly dry then fill in the area with joint compound. Smooth out the area then let the patch dry thoroughly.
You may need to apply two or three layers of joint compound to build up the patched area. Always allow each layer to dry before applying another.
Let the stick and string remain where they are during the patching process. You can remove both just before the material dries.
When the area is completely dry, sand off any high spots using fine-grit sandpaper and a sanding block.
Damaged areas larger than 12 square inches may need a complete replacement panel installed because large pieces of drywall need to be anchored to wall studs or ceiling joists. It depends on where the damage is located on the wall or ceiling and how you had to cut it out. For example, if the space where you removed the damaged drywall exposes studs or joists where it will be possible to secure a patch by screwing it into the stud or joist, you can do that. If not, you may have to replace the whole drywall panel.
To replace the whole sheet, remove the damaged drywall completely, down to the studs. Remove the drywall screws that anchored the old sheet to the studs using a power drill. If there was a lot of water damage, this should be fairly easy; the old drywall will most likely crumble away.
Measure the height and width of the space you’re repairing so that you know how much new wallboard you need. If you need custom-sized panels for an irregularly shaped repair, use your measurements to cut a patch to fit, using a utility knife or drywall saw. Align your new panel with the wall studs and then secure the panel to the studs with drywall screws and a power driver. Use joint tape to cover the seams where each panel meets. Then apply joint compound over the tape, using a putty knife. Let the compound dry for the time specified by the manufacturer and then sand the compound with fine-grit sandpaper until the seams are flush with the drywall panels.
Enlist someone as a helper if you’re putting in whole drywall panels or working on ceiling repairs. Drywall can be heavy, and trying to keep it steady while fastening it in place can be challenging.
Step 4: Prime and Paint
Apply True Value EasyCare® Ultra Premium Interior Primer/Sealer with a large paintbrush or roller applicator. Make sure you cover the entire surface of the wall.
Open windows to make sure you prime and paint in a well-ventilated area.
Pour True Value EasyCare® Ultra Premium Interior Paint into a paint tray and coat your roller or paintbrush. Paint widthwise in 6-ft. square sections, using a zigzag pattern of overlapping "W" strokes. Move from right to left, then left to right, spreading evenly with vertical strokes.
To ensure even coverage, use light strokes to re-roll across the ceiling and paint from the bottom to the top of each wall. If your paint has a flat finish, you don't need to blend. Otherwise, to blend, paint over the entire surface (for very large areas, do two square sections at a time) with one-directional, overlapping, non-diagonal strokes once again.
Using a small, angular paintbrush, do wall brushwork in areas where your roller can't reach, like the corners and next to doors, windows and molding.
If necessary, apply a second coat of paint using the same technique as the first. You don't have to let the paint completely dry between coats, but your results will be better the longer you wait.
Step 5: Clean Up
Use a shop vacuum to clean up dust and debris. Pick up your drop cloths or tarps and close up your paint cans. Dispose of used paint cans appropriately. Cleaning paintbrushes and other tools can be made easy with warm and soapy water. Thoroughly rinse your roller covers and brushes in water until the water runs clear, and then place them in a brush/roller spinner, if you have one, to remove excess liquid. Store in their protective sleeves or hang them on nails or hooks. Pick up drop cloths carefully, making sure not to spread around any paint that may have gotten on them. Remove painter's tape at a 45-degree angle to avoid damaging any fresh paint. Remember that the longer it stays on, the harder it is to remove.
Great job! You’ve withstood water damage and repaired your wall/ceiling.
Project Shopping List
Here’s what you’ll need to complete this project successfully.