Drywall Tapered Edge Inside Corner [Ultimate Guide]

Finishing drywall can be much more complicated than it needs to be if you don’t have the appropriate tools and equipment, or if you rush into certain tasks without actually knowing the best way to go about them, and this includes taping down the edges of the inside corners. 

I always find the inside corners can be a lot harder to deal with compared to outside ones. It’s important that you know how to do it correctly so that you don’t risk causing any damage to the wall and ruining its appearance.

If you’re having trouble tapering down the edge of an inside corner on your drywall, we have the full breakdown right here. We also have a few tips that will make the whole process a lot easier.

As long as you mix your compound thoroughly so that it comes out thick enough, and you apply it evenly across your knife when spreading, it won’t take you long to finish off an inside corner. It will look clean and professional, too.

How To Tape Inside Drywall Corners

Taping down the inside corners of drywall is one of the hardest and most challenging finishing touches.

But it needs to be done, otherwise you’ll have exposed edges that don’t blend with the rest of the wall, being a real eyesore that no one wants to see. 

The good news is that once you know how to tape inside corners and have attempted to do it a handful of times, it becomes much easier.

So, it’s well worth learning, especially since it will make future DIY drywall projects so much easier. 

Here is the equipment you’re going to need before you get started:

• Two-inch thick paper drywall tape 

• Four-inch putty and joint knife (Five or six inches will also work)

• Thinned down all-purpose taping mud 

Step 1 – Prepare The Tape

Start by measuring the tape to the length of your wall. Take one edge of the tape and place it a quarter inch away from the corner bead in the corner of the wall. Stretch this over to the other side which should also be a quarter inch from the corner bead. 

Use the putty knife to cut the strip off, and it will be ready to use when you come to stick it on. Before you place the tape to the side, take a look at the back, and you will see a long crease running through the middle. Use this to fold the strip over so that it’s a little thinner and easier to use. 

Step 2 – Mix The Taping Mud With Water

Now you need to prepare the compound mixture. Otherwise the mud can come out a little too thick and can end up dripping down the wall or looking too big and bulky in the corners. 

To do this, remove roughly a quarter of the compound from its bucket and proceed by adding two to three cups of water. You can mix the water in with the mud by using either a half-inch drill, a special mixing paddle, or a hand-powered giant ‘potato masher’.

Swirl this around for a few minutes until the compound has thinned out and is much easier to lift up out of the bucket. 

Step 3 – Start Spreading The Compound Mud

Once you have mixed your compound well, it’s time to start spreading! Use your putty knife to scoop out some of the mud.

While you can lift this out any way you would like, it’s best to try and get it stuck on a single corner of the knife since this will make it easier to spread without it coming out too thick. 

Spread the compound across the top of the wall from left to right, and try to always keep it only two inches wide so that it remains consistent. If there is any excess, remove it by using the opposite side of the knife. 

Step 4 – Cover The Underside

You will then want to spread the mud across the underside above the strip that you have just covered, and make sure to try and also keep this two inches wide for the sake of consistency. 

This can be a lot trickier, but as long as you press your knife against the wall so that it doesn’t make contact with your first strip, it will work just fine. 

Before you start taping, flatten out both the first compound spread and the one you just placed with your knife to make sure they are consistent. 

Step 5 – Apply The Tape

Grab the tape that you cut and folded over earlier, and attach it to the first sticky mud compound you spread across the wall so that both sides are also a quarter inch away from each end. 

So you can make sure the tape is firmly applied, it can be worth gently running a flat side of the putty knife across the strip and pressing down ever so slightly to ensure that it sticks. 

Step 6 – Check For Any Excess Mud

Once you have run your knife across the taping several times over, have a quick look just to check that there is no excess mud that may have leaked out under the tape.

If there is, wipe this off gently by getting the putty knife as close to the tape as possible without actually making contact with it. 

Summary

From personal experience, I know how annoying it can be taping down inside corners, but once you know how to mix and spread the compound, and the correct way to apply the tape without it stretching over the wall or falling off constantly, it makes this otherwise complicated task a lot easier. 

Frequently Asked Questions