How to Hard Coat Ceilings

Prepare Joint Compound

• 1

  Stir premixed, lightweight joint compound in a trowel using a 12-inch drywall knife.

• 2

  Fold the joint compound over until the texture is smooth and light, without air bubbles.

• 3

  Scoop the joint compound out of the trowel using the 12-inch drywall knife.

Apply the Joint Compound

• 4

  Apply the joint compound to the ceiling, at the corner of the room.

• 5

  Place the blade of the 24-inch drywall knife at the corner of the ceiling, where the wall meets the ceiling, at a 45-degree angle.

• 6

  Smooth the joint compound across the ceiling in a straight line, 3 feet long, in one continuous motion.

• 7

  Place the 24-inch blade where the wall meets the ceiling above and slightly overlapping the first row.

• 8

  Drag the blade across the ceiling, parallel to the first row, eliminating as many lines and indentions as possible.

Smooth the Joint Compound

• 9

  Blend each 3- by 3-foot sections together using the 24-inch knife.

• 10

  Add joint compound to the ceiling with the 12-inch knife as needed.

• 11

  Mist stubborn areas with water from a spray bottle to manipulate a smooth surface.

• 12

  Blend each row into the next, working in manageable 3- by 3-foot sections until the ceiling is covered.

Sand the Joint Compound

• 13

  Allow the joint compound to dry according to manufacturer instructions.

• 14

  Sand the ceiling with a ceiling pole and 120-grit sandpaper.

• 15

  Use a moist sponge to remove grit.

Repeat

• 16

  Apply a second and third coat of joint compound until all the low points are filled.

• 17

  Sand between coats until imperfections are minimized.

• 18

  Sand the last layer with 220-grit paper for a smooth finish.