Ceilings often look uneven and ridged. This is partly due to how light cuts across a ceiling, especially at night. The shadows cast by bright or elevated lights heighten ceiling flaws, sometimes making them look worse than they do during the day, when ambient light from outdoors softens the shadows. Other times ceilings have prominent ridges that you must camouflage with multiple coats of joint compound. Deciding where to place the joint compound and how much to use might be difficult, and you might have to perform many consecutive coats to make the ceiling look smooth and even.
Instructions
1. Use a contractor's pencil to mark the center of all prominent ridges. If you have trouble spotting ridges due to ambient light, mount a bright halogen light at one end of the room so its light cuts across the ceiling. This should highlight any significant ridges, allowing you to mark them with a contractor's pencil.
2. Spread joint compound on both sides of each pencil mark. Use a 12-inch drywall knife for maximum coverage. Apply enough joint compound to soften the curve of the ridges by filling in the depressions next to them.
3. Let the joint compound dry for 24 hours.
4. Sand the dried application with 100-grit sandpaper. Focus on removing lines made by the knife and surface blemishes but don't remove so much joint compound that you reveal the ridge.
5. Apply another coat of joint compound over the original application to soften the ridge more. Allow the compound to dry and repeat the coating process as necessary until the ceiling looks even and level.
6. Use 150-grit sandpaper to smooth your work and prepare it for primer and paint.
Tips Warnings
Some ridges require six or seven separate coats, while others require only two or three. For ceilings with many prominent ridges, the scale of the project might make hiring a professional drywall finisher a wise choice.
