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How to Finish Drywall Like a Pro

Every house, at one point in time, needs a repair made to a drywall or plaster wall or ceiling. To save money, you may have tried this and ended up cursing worse than a drunken sailor. Working with drywall compound has broken up many a marriage.

I’ve finished new drywall for years and patched more than I care to remember. I’ll tell you now it’s a tough job to get professional results, but it’s possible. You just have to know a few secrets that were taught to me decades ago by a few expert drywall finishers. You also need to be patient and practice.

You can watch a nice short video of me showing how to finish drywall by going here:


Degree of Difficulty: hammer-5-5

Step One: You’ll need a 5-inch flexible drywall taping knife, a 10-inch flexible drywall broad knife, a mud pan, pre-mixed drywall all-purpose compound, paper drywall tape, and a drywall sanding pad.

Step Two: The first step is to mix up the joint compound so it’s the right consistency. The compound from the factory is always too stiff. Add water in small amounts only mixing up the top layer in the new bucket. The consistency of the mud should resemble warm cake icing that is very easy to spread.

Step Three: Apply a layer of the compound over a seam or crack that needs to be repaired. The layer of compound should be one-eighth-inch thick and uniformly smooth. Embed a piece of the paper tape into the compound and use the 5-inch knife to pull out excess compound from under the tape. You want to only remove half the compound you originally applied making sure there is at least a one-sixteenth-inch layer of compound under the tape. If you remove too much compound from under the tape, you’ll get blisters in the tape when you apply the second coat. Allow this compound to dry for a day or two.

Step Four: The second coat of compound is the hardest to apply. It requires a deft hand and great hand-eye coordination. Use the 10-inch knife to apply a layer of compound over the entire taped seam with the compound extending at least 2 inches either side of the edge of the paper tape. The compound should be approximately one-eighth inch thick over the paper.

Step Five: Holding the knife at an angle and applying pressure so one tip of it is touching the drywall where there is no compound, pull the knife at an angle across the compound much like a snow plow plows snow. The other tip of the knife should be up in the air so that it’s creating a ridge of compound over the center of the paper tape. The thickness of the compound above the center of the paper tape should be just over one-eighth of an inch. The creamy consistency will allow you to feather the edge of the compound to nothing below and above the taped seam.

Step Six: Step two will produce an ugly uneven ridge of compound over the center of the paper tape. Don’t worry about this. When the second coat dries in a day or two, you’ll lightly sand off this ridge before applying the final coat.

Step Seven: When the second coat of compound is completely dry, sand off the center imperfection on top of the now-hidden tape. Brush off any dust. Use the 10-inch knife to apply the third, and final, coat of compound. Apply a thin one-sixteenth layer of compound over the entire area where you’ve previously applied the compound. Hold the knife at a slight angle and pull it across the seam removing almost all the compound you just applied. This coat will fill in any minor imperfections in the compound.

Step Eight: The third coat will dry rapidly if the humidity is low. You can now sand the seam and inspect it for any imperfections. Repeat Steps Seven and Eight, if necessary, to get a smooth surface at all the seams.

Summary: It requires lots of practice to get professional results. The key is making sure the joint compound is the correct consistency. If it’s too thin, it will fail. If it’s too thick, you’ll fight it every step of the way. The biggest mistake you can make is leaving too much compound on top of a seam causing you to have to sand forever and ever. It’s easy to add more compound. It’s hard to sand it off.

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One Response to How to Finish Drywall Like a Pro

  1. Trick from old time rocker. Mix a diluted soup of white glue & water (now, you can buy cans of spray on colored adhesive). Paint the seam with the slurry, tape with moist tape, paint the tape with an overcoat of glue. Tim, this trick prevents the tape pulling up as you coat with compound. From there, your instructions are right on. I keep a spray bottle of water handy for those times when the compound dries too quickly. Once I think the job is finished, I go over each seam with a bare hand to check for imperfections that the eye can't see. One last comment, a good selection of knives, both straight and angled makes the job so much easier. Taping can be simple or a curse - it is patience that makes the difference. I am a do-it-yourselfer and have taped my projects for 30+ years (to include an entire house.) Only time I had trouble was when I pushed the job and got sloppy.

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