BROWSE HOW TOs

How to Apply a Smooth Coat to Drywall

By eHow Home & Garden Editor

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Applying smooth coat, or skim coating, is the final step in your preparation before priming and painting your walls and ceiling. It requires a careful eye, but with a little practice you can give surfaces that professional look.

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Instructions

Difficulty: Challenging

Things You’ll Need:

Drywall Compound
Drywall Trowel And Knives
Sanding Blocks

Finish Coat on Walls

Step1

Sand all joints smooth.

Step2

Check joints for uneven spots (depressions, humps, ridges and waves). Hold the edge of a mud knife across a joint and try to rock the knife back and forth. If you get a rocking motion, you'll need to feather the joint out farther.

Step3

Feather the joint out if necessary. ("Feathering" refers to the process of spreading the drywall compound out to a wider and wider, ever-thinning edge. It's a trick used to keep the eye from noticing the slightly higher center of the joint.)

Step4

Sand the joint if one side is too high, or feather more drywall compound (a.k.a. "mud") on any low spots.

Step5

Let dry and check again, repeating steps until smooth.

Finish Coat on Ceiling

Step1

Sand all joints smooth.

Step2

Apply a thin layer of mud over entire ceiling. Use a 12-inch-wide trowel and, with even pressure, smooth mud over ceiling.

Step3

Go back over area with trowel until smooth. You'll remove most of the mud, leaving only a very thin layer.

Step4

Allow this coat to dry.

Step5

Sand the entire ceiling to remove any rough spots.

Step6

Turn a light on and step back at an angle and look for any uneven areas on the ceiling.

Step7

Sand the area or apply more mud if you have uneven areas.

Tips & Warnings

If your mud is too thick to spread evenly, you can thin it with water. Do not make mud so runny that it doesn't stay on your knife, and remember: thin mud is weak mud.
Applying a smooth coat of mud to the ceiling is a very challenging job. It may require several coats.
Wear safety glasses and dust mask when sanding joints. The dust can be harmful to eyes and lungs.

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Comments

jcjrcrew said

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on 10/11/2008 I was repairing a large area of my ceiling. I mudded and sanded 3 times and felt it looked smooth. When I applied 2 coats of paint I can see the entire patch. I didn't use primer. I persume that was a mistake but now do I sand over the painted repair or what? Would appreciate your help. Thanks

Anonymous said

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on 8/28/2006 I would never recommend dry sanding a Sheetrock repair. The dust just gets everywhere! Been there, done that.

I usually plan on mudding over a patch 3 times to get the right finish. When the mud is completely dry, I cut up an old T-shirt and with a bucket of water handy, I feather out the final finish.

Anonymous said

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on 8/8/2006 I do a lot of repair work, and homeowners like that I do not create dust. With a little practice; use a large car cleaning sponge to wet sand your work. Depending on the smoothness of the sponge and mudding, you can feather your work nicely. Move in a circular motion with a lite touch. Using a bright light at a sharp angle to the wall will show you the area in need of work. Use a bit of watered-down mud on large indentations. Then sponge those areas again when dry. It takes a bit longer to do it the wet sponge way, but with no dust everyone likes that.

Anonymous said

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on 11/22/2005 On the final coat, cover the entire joint with enough compound to cover it. Don't worry about it being smooth. Spray it with a light coat of water from a spray bottle. Use a knife wider than the joint and smooth the whole joint with as long a stroke as possible. This also feathers the edges nicely. After it's dry, get a cheap rattle can of flat black (preferably lacquer), and spray a light dusting on the joints. Sand till you see no more black. That takes out the guess work. The black paint is a common practice in auto body repair shops. If done right, one light sanding is all it needs.

Anonymous said

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on 6/11/2007 Add a little dish soap to your compound mix and stir it well. It will help eliminate those annoying bubbles and it smells nice when you're mudding.