Repairing a Straight Line Crack in Drywall

Use a utility knife to cut a groove along both sides of the crack and then clean out any loose debris from inside the crack.

Push on the edge of drywall where the crack is. If the drywall moves, even slightly, this is the cause of the crack. Use a hammer and drywall nails to tightly secure the drywall to the stud.

Apply mesh joint tape over the area of drywall that is cracked. The advantage of mesh tape is that it is self-adhesive and easier to work with than traditional paper joint tape.

Open the joint compound and scoop it out with the 10-inch drywall knife and load the mud pan. Use the top edge of the mud pan to scrape off any excess mud on the drywall knife.

Load the drywall knife with joint compound and apply the first coat to the wall. To do this, hold the drywall knife with the blade side pointing toward the ceiling and keep a firm grip on the handle of the knife, with your index finger pointing up on the handle. This will help you keep better control of the knife. Slowly pull the knife down along the crack with moderate pressure to apply a thin coat of joint compound.

Apply additional coats of joint compound on each side of the first strip of compound over the crack.

Feather out the compound by running the drywall knife down the middle of the compound. On the first pass, your index finger should be placed left of the center of the handle, to feather to the left. On the next pass, move your index finger to the right and smooth out the compound.

Wait for the first coat of joint compound to dry. The amount of time it will take depends greatly on indoor temperature and humidity levels.

Run the drywall knife over the dried compound to scrape off any harsh edges. Only use moderate pressure, as pushing down too hard can leave grooves in the compound.

Apply a second coat of joint compound the same way you applied the first coat and allow the compound to dry.

Use a fine-grit sanding sponge to sand the patched area of drywall so it is smooth and seamless. Apply minimal pressure and do your best to only sand the hardened joint compound. Sanding the paper top of the drywall can tear the drywall and damage it. To check your finished product, close you eyes and run you fingers over the area. Take note of any harsh edges or bumps and sand those areas again.

Prime and paint the patched area according to the manufacturer's instructions on the specific primer and paint you are using.