Blowing Rock sits in a cold-severe climate zone, and that matters more for panels than people expect. Foam-injected steel sections from the 1980s take on moisture at the seams over decades, and repeated freeze-thaw cycles push that moisture into small cracks that widen every winter. You'll see it as a section that looks fine in July and shows a hairline split or a soft spot by March. Dents from ice buildup or snow load are common too - a corner takes a hit, the steel skin creases, and the foam core behind it stays compressed even after the dent's been knocked out. On a door built around 1984, you're also looking at seams that have been through forty winters of expansion and contraction, which is where rust starts even on doors that were never dented at all. None of this is a Boone problem or a Blowing Rock problem specifically - it's a cold-climate problem that shows up fastest on the oldest steel.