How To: Finish Drywall Joints

How to Finish Drywall Joints

Photo: Kit Stansley

Most of the time finishing drywall joints isn’t one of those jobs that has people jumping up and down with excitement. Even with a decent amount of drywall experience under my belt, when faced with the 2000 square feet of unfinished drywall in my current house, all I could picture was a lot of sanding in my future. Like, for all of eternity. Luckily I had a great mentor to teach me some of the tricks of the trade, and in no time my joints required very little sanding for a perfectly smooth wall.

GETTING STARTED

Before you can finish drywall joints you need to have actual wallboard in place. You can learn how to install drywall here. The thing to keep in mind is that a sheet of drywall has slightly beveled ends which make finishing joints much easier. When hanging the boards it will be tempting to use small scraps to finish things off, but you’ll be hurting yourself in the long run.  Always try to use the factory edges to create your joints.

Now, let’s talk mud.

What You Will Need
Now, I never turn down a good excuse to add to my tool collection, but this is one instance where having the right tools will mean the difference between a good drywall joint and losing your sanity over a sanding block.
- Mud pan
- 6″ drywall knife
- 10″ drywall knife
- Drywall tape
- Lightweight joint compound
- Sanding block

How to Finish Drywall Seam - Mud Pan

Photo: Kit Stansley

Now, let’s talk mud.

INSTALLATION

Step 1: Mixing Joint Compound
Joint compound comes in two forms: ready-mixed and powder. You can use either, but I prefer the ready-mixed variety for convenience. You will need to stir the compound to loosen it up and make it easier to work with. You can do this with a mixer attachment to the drill or use the drywall knife (and some elbow grease). A little bit of water at the ready will also help get the mud to an easy-to-work-with consistency, loose enough to spread on the wall without running.

How to Finish Drywall Joints - Mixing Compound

Photo: Kit Stansley

Step 2: Taping The Joints
You can use paper or mesh tape to finish the joints. Mesh tape is usually self adhesive and can go right on the joints.  For paper, you will need to apply a thin coat of mud to the joint, apply the tape, and press into place with the drywall knife.  It’s a good idea to let paper tape dry overnight before finishing off the seam.  Mesh tape can be finished immediately after installing.

Step 3: The Three Swipe Method
I’ve always been pretty conservative with how much mud I put on the seam, because like everyone else in the universe, I didn’t want to spend the rest of my life sanding it down. However, getting enough joint compound on the wall is key. This is how much should go on the seam to start.  

How to Finish Drywall Joints - Three Swipe Method

Photo: Kit Stansley

I know, I know, even seeing that much mud on a seam in a picture gives me sanding anxiety too. However, the three swipe method is all about putting a lot of mud on to start and then taking away the extra.

First, “feather” the top edge of mud by holding just the top edge of the knife tight to the wall and drawing it smoothly across the seam (Swipe 1).

How to Finish Drywall Joints - Swipe One

Photo: Kit Stansley

Then do the same to the bottom with the bottom edge of the knife (Swipe 2).

Finish it off by going over the whole joint with one smooth stroke while keeping the knife flat to the wall (Swipe 3).

How to Finish Drywall Joints - Swipe Three

Photo: Kit Stansley

The beveled edge of the drywall retains more mud in the middle of the seam than on the top or bottom. Between swipes, be sure to wipe both sides of the knife on the pan. Dried clumps of drywall are your enemy at this point.

Once the first coat is dry you’ll need to repeat the process, making the finished coverage about 12″ wide. You can use a sanding block to smooth away any imperfections between coats and after the final coat.

As with anything, experimentation and practice will help you perfect the technique of finishing drywall joints. But, follow my three-swipe method and you too can have smooth joints without losing your sanity to sanding.

To find out more about drywall installation and finishing, consider:

How To: Choose Drywall
Installing Mold-Resistant Drywall
Patching Damaged Drywall (VIDEO)