If it makes you feel any better...we have those all over our house. The previous owners did a cheap, crappy, tape and paint job shortly before they sold it. No mud, no nothing, just tape and paint over it. Within six months, it all started peeling and moving. Thanks, folks
. I don't consider it much more than a cosmetic problem. The house has been here, as is, for 33 years, with plenty of snow on the roof, wind, etc... Settling is long done. The actual gap between the walls and the ceiling (from truss uplift and shrinkage), what they were trying to cover, gets better in the summer (when everything is humid and swollen, we don't have central air) and worse in the winter, when everything dries out and we're dealing with heavy snow load and high winds. Taping and painting over it just made it uglier than it had to be.
A painter who has worked on other things in the house tells me that to do away with it, I'll need to take down all the tape and redo it right, with some caulk that can expand and contract when the house/drywall moves a bit and repaint. I don't have the blood sugar for that right now, and we'll be here for a while, so I'm just pretending I don't see it
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