Nail pops are one of the most common drywall-related complaints from homeowners. They're a readily visible flaw, and as with many drywall issues, homeowners consider them an indication of their home's overall level of quality.
A nail pop occurs when the point of attachment between the drywall and the wood framing fails. A nail pop can be either concave or convex, depending on whether the drywall moved and the fastener didn't, or the fastener moved and the drywall didn't. In both cases, the result is a nail pop. A nail pop looks like a small dent or bump on the surface of the wall.
Drywall adhesive is a great way to help eliminate nail pops altogether. Drywall adhesive bonds drywall to surfaces, such as wood and metal studs, reducing the number of fasteners required and helping to eliminate some of the problems that cause nail pops. The adhesive can also bridge minor imperfections in the framing.
Cause 1:
Drywall incorrectly attached
Fasteners may move if the framing isn't flush and aligned with adjacent framing members. In addition, if the drywall isn't driven flush with the wood framing, it can travel along the fastener as the framing expands and contracts, causing a nail pop. This movement may occur due to:
- Poor setting of the fastener
- Wet wood (and its subsequent shrinkage)
- Twisting wood
- Adhesive lines that aren't adequately compressed
- Insulation cavity fills that hold the drywall off of the framing face
Solution
Inspect the alignment of the framing, and identify any areas that aren't flat prior to hanging drywall; misaligned framing won't allow the drywall to sit flush against the framing. Then, have the framing crew correct any misaligned framing to create a flat surface for the drywall. When drywall is hung, make sure the installers follow the fastening schedule and use fasteners of the appropriate length for the sheet thickness.
Cause 2:
Lumber with a high moisture content
Lumber may have a moisture content of 18% or higher when it’s installed, a condition typical of southwest lumber. When lumber has a high moisture content, it will shrink as it dries. Lumber that shrinks after drywall is installed will create a space between the drywall and the framing that may later lead to nail pops. The lumber can also twist as it dries, making fastener locations visible.
Solution
Follow a three-step strategy to install lumber with a high moisture content. Prior to framing the home, store the lumber on risers placed on level ground and keep it covered. Apply the roofing underlayment and shingles as soon as possible after framing to minimize the framing's exposure to bulk water. If the framing still has a high moisture content, allow adequate drying time prior to installing the drywall. Using screws instead of nails will also help reduce nail pops due to moist lumber.
Cause 3:
Framing cavities overfilled with insulation
Insulation, especially spray foam or blown-in cellulose, can fill a wall cavity beyond the face of the framing. If drywall is installed over these insulated areas, the pressure of the insulation against the interior face of the drywall may cause nail pops.
Solution
Inspect all framing cavities before installing drywall to make sure that the insulation has been installed flush with the face of the framing.
