How to Install and Finish Drywall

Understanding Drywall Size and Stud Layout

With studs spaced 16 inches on centre, a 48-inch-wide drywall sheet spans three 16-inch framing bays, with its two outside edges supported on stud centre lines.

When wall framing is built with studs spaced 16 inches on centre, the 48-inch width of a drywall sheet follows the framing layout.

With properly installed framing, a 48-inch-wide drywall sheet spans four stud positions from one edge to the other.

Choose the Correct Drywall Screws

Drywall should be installed using proper drywall screws. The type of screw depends on whether the wall is framed with wood or metal studs.

Set the Screws to the Correct Depth

The drywall screw head should sit slightly below the surface of the drywall paper. This creates a small depression that can later be filled with joint compound.

However, the screw should not be driven so deeply that it tears through the drywall face paper.

Measuring and Cutting Drywall

Straight drywall cuts can normally be made with a standard utility knife.

1. Measure the required size and mark the drywall.
2. Place a long straight edge along the mark. A long level can be used, but a 48-inch drywall T-square makes the process easier.
3. Run the utility knife along the straight edge and score the drywall face paper.
4. Snap the drywall panel along the scored line.
5. Cut the remaining paper on the back side with the utility knife.

Position the Drywall Sheets Correctly

Whenever possible, plan the drywall layout before fastening the first panel.

Factory tapered edges should preferably meet factory tapered edges.

These edges are manufactured slightly thinner to create space for drywall tape and joint compound. This helps produce a flatter finished joint.

A cut edge meeting another cut edge creates what is commonly called a butt joint. Butt joints can be finished properly, but because there is no factory recess, the joint compound usually needs to be feathered over a wider area.

How to Apply Paper Drywall Tape

1. Inspect and clean the drywall joint.
2. Apply an even layer of joint compound over the joint using a taping knife.
3. Centre the paper tape over the joint while the compound is still wet.
4. Starting near the centre, run the drywall knife along the tape toward the ends.
5. Remove excess compound and trapped air while leaving enough compound underneath the tape to create a proper bond.
6. Make sure the tape is flat without bubbles, wrinkles or loose edges.

Using Paper Tape on Inside Corners

Paper tape is particularly useful for inside corners because most drywall paper tape has a factory crease running through the centre.

Apply joint compound to both sides of the inside corner, fold the paper tape along its centre crease, and carefully position it into the corner.

Embed the tape into the compound while removing excess compound and trapped air.

How to Apply Fiberglass Mesh Tape

1. Make sure the drywall joint is clean and reasonably free from dust.
2. Centre the self-adhesive mesh tape directly over the joint.
3. Press the tape onto the drywall and keep it straight.
4. Apply the appropriate joint compound over the mesh.
5. Press the compound through the openings in the mesh so the joint underneath is completely filled.
6. Smooth the compound and feather the edges into the surrounding drywall.

Tools for Applying Joint Compound

For basic drywall finishing, it is useful to have at least two drywall knives: a smaller taping knife and a larger finishing knife.

A drywall mud pan makes it easier to hold and work with joint compound while moving around the wall.

Choosing Joint Compound

Ready-mixed all-purpose joint compound is convenient because it comes prepared for use and can be used for many common drywall finishing applications.

Setting-type compounds are supplied as a powder and mixed with water. They harden chemically and are available with different approximate setting times.

Cover the Drywall Screw Heads

Every drywall screw head must be covered with joint compound.

Take a small amount of compound on the smaller drywall knife and pull it firmly across the screw depression.

Completely fill the depression while leaving as little unnecessary compound around the screw as possible.

The Three-Coat Drywall Finishing Process

Sand the Finished Drywall

After the final coat has completely dried, sand the finished areas until the transitions between the joint compound and drywall are smooth.

Approximately 150-grit drywall sanding material works well for general smoothing.

For a finer final pass, approximately 180–220 grit can be used.

Use light pressure and be careful not to expose the tape or damage the drywall face paper.

Drywall Is Ready for Primer

Once all joints and screw heads are smooth, inspect the wall carefully and remove the drywall dust.

The drywall is now ready for drywall primer.

Primer is important because bare drywall paper and joint compound absorb paint differently. Priming helps create a more uniform surface before the finish paint is applied.

After the primer dries, inspect the wall again. Primer can make small imperfections easier to see, allowing them to be corrected before the final paint coats are applied.