How to Repair a Knockdown Ceiling
- 1). Lay drop cloths on the ground to prevent unwanted spills. Wear gloves, goggles, mask, and protective clothing as well.
- 2). Scrape off any loose or damaged particles of the ceiling with a joint knife. Hold a piece of cardboard underneath to catch the falling debris. This will create a clean surface for the new layer of compound to adhere to.
- 3). Pin a plastic tarp to the ceiling around the four sides of the damaged section using push pins allowing the tarp drape four feet down from the ceiling. Even if the damaged area is a circular shape, create a four-sided barrier with the tarp for a more accessible working space.
- 4). Mix joint compound with water to the consistency of pancake batter and pour the mixture into a hopper gun.
- 5). Test the pressure and mechanism of the hopper gun on a piece of cardboard.
- 6). Spray stain-blocking primer on the ceiling. Let the primer dry completely.
- 7). Spray the joint compound with the hopper gun on the ceiling, directing it into the damaged section. Move in steady, continuous movements to avoid overspray in one spot. Let the compound dry for 30 minutes until tacky.
- 8). Flatten the dollops of compound with a trowel. Press the trowel at an angle to avoid flattening out the dollops completely. Let the compound dry for 24 hours. Prime and paint as needed.
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