What is a skim coat?

Drywall professionals use a skim coat to hide imperfect taping jobs and make walls super smooth for the application of satin and gloss paints that reflect light and make unevenness stand out. Some consider skimming walls a job for the professionals who use hawks and trowels. But if the job is small or you just want to try your hand at it, here are the four basic steps to skimming uneven drywall the weekend warrior way.

Supplies

Drywall primer

All-purpose joint compound

Heavy nap paint roller (½ inch+)

Squeegee knife

Mud pan

Damp rag

120-grit sandpaper.

1. Prep

Prepare the walls by coating the entire area with water-based, stain-sealing drywall primer to promote better adhesion of the drywall mud. If your wall is riddled with holes, fill them with joint compound and allow to harden before skimming. Allow the primer to dry completely before moving ahead.

2. Roll

Mix the all-purpose joint compound to the consistency of mayonnaise.

Using a heavy nap paint roller (at least ½ inch), roll the mud directly onto the wall in a thin, even coat working in 4 ft. x 4ft. stacked sections. Because you will be applying multiples layers, there is no need to fill in dips with a thick coat.

3. Smooth

With a damp rag and mud pan handy, smooth the mud with a squeegee knife. Begin from one of the top corners and move the knife downward, overlapping each vertical pass. Using the rag, wipe the knife clean of excess mud every few strokes.

As you move to the bottom of the stack sections, repeat the same process starting from the bottom corner and pulling the knife upward. When the compound makes a ridge between the two sections, use a putty knife to scrape it away horizontally.

4. Layer

Depending on the severity of the imperfections, your wall may require 2-4 layers. Let each layer dry completely before moving onto the next. Move the squeegee knife horizontally on the second coat. Trowel every successive coat perpendicular to the last.

5. Sand

Hopefully, this drywall skimming method has left you with very few peaks and valleys. To finish the wall and prep it for paint, sand the wall with 120-grit sandpaper to give it the finishing touch.