With 4,331 owner-occupied houses across this service area, most of them built before openers were sized for double-wide steel doors, the mismatch is common, not rare. It isn't a Boone quirk exactly - it's what happens when a mountain town's housing stock skews toward the 1960s and 70s across the ten communities we work in, from Blowing Rock down the road to Crossnore twenty miles out.
Blowing Rock is six miles up the road, Banner Elk twelve, and homes in those towns share the same building era as Boone's. A kit engineered to a code written in 2020 doesn't know that. It assumes a rough opening that matches current lumber dimensions and a header carrying load the way today's span tables say it should. In a house from 1979, that header might be doing the job with different lumber, a different span, and forty extra years of settling nobody measured.
So the failure isn't really about installation skill. It's a mismatch between what the door assumes and what the house actually offers. Anyone installing here without checking the opening against the house's actual age is installing blind.