Seal up your ceiling
Finding a leak in your ceiling is never a pleasant surprise. Whether it's due to a leaky roof, a burst pipe, or an unexpected downpour, water-damaged ceiling plaster can become a stressful eyesore. In this guide, we'll walk you through the process of bidding farewell to any stubborn stains, unsightly cracks, and annoying bubbles—a DIY project that can be completed in just one weekend.
Before you begin to repair your water damaged ceiling plaster, confirm that you have fixed the ceiling leak or you’ll be repairing the damaged area again in a short while.
If you don’t know where the leak is, look around your home for other signs where water could be getting in—ceilings are often damaged due to water leaks from the roof, plumbing, or HVAC systems. Walk around the exterior and see if there are any discolored shingles, or use a moisture sensor to find areas with higher moisture and humidity.
With a plumbing leak, you’ll want to shut off the water supply to the pipe as soon as you can. In the case of an HVAC malfunction, shut off power to the HVAC system. After you are confident you have shut off the source of the water, give the plaster time to dry out before proceeding with the repairs.
Any damaged materials—paint, plaster coats, lath—need to be removed. Using a putty knife, lift away any flaking paint or damaged plaster. The material should be soft and easy to dig out and discard. Work your way outward from the innermost area of damage, removing all soft material until you reach hard plaster. At this point, give the area a quick cleaning using a stiff nylon brush, and sweep away any dust and debris.
Push on the ceiling area around the damaged section and see if it feels weak. Any area that moves or gives under your hands should be secured to the lathe with 1-5/8 inch drywall screws so it doesn’t buckle.
Coat the area with an oil-based or quick-dry primer-sealer. The primer will prevent any stains from bleeding through your paint, and help the patching compound bond better. Coat the entire affected area with the primer, and let it dry before moving on to the next step. Most primers require 24 hours to dry, but quick-dry primers dry in about one to two hours.
Using a 6- or 8-inch drywall knife, apply joint compound to any cracks or gaps present. If you are repairing a large area, you can use a long, thin board such as a piece of lattice molding to go over the area with the joint compound in one large sweep. This will also help you smooth our the application. Allow the joint compound to dry for 24 hours before proceeding.
With some coarse or medium sandpaper, smooth out any bumps or small imperfections in the joint compound. Use your nylon brush to sweep away any dust or debris and wipe the area clean with a damp rag or sponge.
Apply a second coat of joint compound in the same manner as before. Make sure to completely fill in the deeper parts of the damage. You should only apply a thin area on top of the unaffected spots surrounding the main source of the damage. Let the second coat dry.
Sand the area one more time, with 120-grit sandpaper. Wipe the area clean once again, and prime is once more using your primer-sealer. This last coat of primer-sealer is essential; it should prevent any residual water from preventing the fresh coat of paint to bond. Allow your primer-sealer to dry before applying your latex paint.
The cost for professional water damage restoration to your ceiling is $350 to $2,000, on average, and depending on how extensive the damage is. A small, isolated area of damage—one where you can quickly identity and shut off the water source—is an easy weekend DIY task, but for major fixes, it’s always better to call in a professional water restoration expert. Water damage can quickly grow from a small problem to a big one, so don’t hesitate to investigate getting expert help.
Look for flaking paint or air bubbles that burst and then flake away. Paint will begin to flake after being exposed to minimal moisture or water, so it’s a good indicator of any water damage. If you notice your paint starting to flake, feel the plaster underneath to see if it is soft or damp.
Yes, mold can grow on virtually any porous material, including plaster, and can be a pain to get rid of. If you see any signs of mold or mildew growth, call a local mold inspection company to take a look—mold is a health hazard and can spread quickly to other parts of your home.
