Nail pops occur in walls and ceilings when the nails or screws holding the wallboard to the framing loosen, this allows the wallboard to move and the nail heads to push through the surface, causing an unsightly blemish. Using the repair technique on this page the wallboard can be stabilized and the pop permanently repaired.
First, locate the framing behind the wallboard. In many cases there will be several nail pops in a row, indicating the direction of the ceiling joists or wall studs underneath. If only one nail pop exists, determine the direction of framing by looking in an attic or other exposed area. Otherwise, tap the wall or ceiling and listen to find the framing. In general a hollow sound indicates a space behind the wall, the difference between this hollow sound and the sharper sound of hitting the wall over a stud, gives one a rough idea of the location of the framing. Using this method you should be able to determine which direction the framing runs.
Drive 1 5|8 inch drywall screws through the wallboard and into the framing on both sides, and about 2 inches from the nail pop. Drive the heads far enough to sink them slightly below the wall surface. You can do this with a screw driver in cases where only a few nail pops are involved. If you have many nail pops to repair, a cordless drill-driver will save a lot of time and effort.
The best way to ensure that loose nails will not pop again is to remove them, however, if pulling the nails will cause more damage, sink the heads instead using a hammer to drive them well beneath the wall surface. In any case, "dimple" the drywall surface over the pop using a hammer to crush the gypsum, making a depression that can be filled with joint compound to cover the damage and level the surface.
If the wallboard around the nail pop is ragged or crumbling, remove all damaged drywall paper and gypsum material using a sharp drywall knife to cut it away. To be sure the drywall paper won't pucker up and separate with the repair compound, seal the surface with a shellac-based primer-sealer and let it dry for about an hour before proceeding with the repair.
You can use setting-type or ready-mixed joint compound for this repair. The setting compound will dry faster and be harder than ready-mixed, but it must be mixed with water before using making the ready-mixed easier to use.
Use these instructions for mixing and handling joint compound and cover the pops and the new screw heads with a thick coat. Spread the mud to overflowing over the depressions and immediately skim off the excess using a joint knife held at about a 30° angle.
Press down hard enough with the blade to remove most of the mud, floating it over the depressions and leaving a very thin coat on the surrounding wall to avoid a lot of unnecessary sanding when you're done. Return the collected mud to the pan and move on to the next pop. When you're done, let the mud dry completely before proceeding.
It will take at least two, and possibly three, coats of mud to level and smooth out the dimples. Let the mud set and dry for about 30 minutes if you're using setting compound, if you're using ready-mixed, wait an hour or more for it to dry before proceeding.
Before applying a second coat over the pops, scrape off any roughness in the dry mud using the joint knife with an upward stroke. Apply a second coat of mud, spreading it thick first to completely cover the area, and then skimming the excess off to level and smooth the surface.
When the second coat is dry, examine the patch to determine if another coat is needed and apply a third if necessary. Apply the mud as before, spreading a thick coat first and then skimming off the excess to smooth it. When the final coat is dry, lightly sand with medium grit sandpaper, feathering the edges into the surrounding wall or ceiling surface and smoothing the patch over the dimples.
To finish, brush away the sanding dust, wipe off the residue with a damp rag and touch up the paint. If you're using flat latex finish paint, you can use it to prime the repair. If you are using semi-gloss or other shiny paint, prime with flat latex paint or a latex primer first.