Most of the houses we install into were built between 1956 and 1979, median year 1970, and that matters for two reasons. First, openings from that era were framed for doors that don't match what's sold today - narrower tracks, different header heights - so a straight swap often isn't straight at all. Second, this area sits in a severe cold climate band, and original doors from that period were rarely insulated. Thirty, forty, fifty winters of freeze-thaw on an uninsulated panel warps steel, cracks wood, and stresses hardware that was never rated for the temperature swings we actually get. By the time a homeowner calls us, the door usually isn't broken in one spot - it's tired everywhere at once, which is a replacement conversation, not a repair one.