How to Paint Drywall Corners

Do not use a plastic drop cloth in place of a fabric one.

Along corners, portions of drywall are joined with a specific type of thick paper. This paper is coated with spackling paste or drywall mud to hold it in place. This makes the wall look seamless, and camouflages gaps between the two sections of drywall. Unfortunately, the paste and drywall mud absorb paint much slower than the bare drywall that surrounds them. This makes them show through along corners in the final finish. Professional painters call this "flashing through," and the only way to prevent it is to apply a special drywall sealer before painting.

Things You'll Need

• Blue painter's tape
• Heavy-duty fabric drop cloths
• Drywall sealer
• Roller frame and nap covers
• 3- to 4-inch latex paintbrush
• Roller pan
• Satin latex paint

Instructions

1. Cover baseboards and trim with painter's tape.

2. Cover the flooring adjacent to the wall with fabric drop cloths.

3. Apply the drywall sealer to the walls with a roller. Apply the sealer to the corners with a latex paintbrush.

4. Allow the sealer to dry for four hours.

5. Clean all painting tools with water.

6. Apply a coat of latex paint to the sealed walls with a roller. Use a fresh, clean nap cover. Apply a coat of paint to the sealed drywall corners using the brush.

7. Allow two hours for the paint to dry, and then apply an additional coat.

Tips & Warnings

• Drywall must be coated with a sealer, or the spackling paste or drywall mud will show through the paint along the corners.

• Do not use a cheap, plastic drop cloth because paint tends to pool up on it, which can lead to messes.

Resources

• Popular Mechanics: 5 Pro Painting Tips Every Amateur Should Know