A. Myron Ferguson, a drywall contractor in Galway, N.Y., responds: It takes about 1,000 screws to hang 1,000 square feet of drywall, so it’s not uncommon to have a dozen or so screw pops in an average house.
Screws set too deeply might be fine when the drywall is sanded, but may pop when there’s structural movement or an impact. Also, insulation can push against the drywall and prevent it from being fastened tight to the framing; later, pressing the drywall back against the framing can cause pops to occur. And finally, when framing dries and shrinks...
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