Shingles lift up due to a combination of wind, age, adhesive failure, and installation issues. The most immediate cause is wind getting under the shingle edge and breaking the factory-applied thermally activated sealant bond that holds shingles together. Once this seal is broken, the shingle remains lifted and vulnerable to further wind damage. This is common after high wind events or if shingles were installed in cold weather below 40 degrees and never properly sealed. Age is another major factor, as after 15 to 20 years the sealant loses strength, granule loss makes shingles lighter, and the asphalt becomes brittle, allowing wind to lift them easily. Improper installation causes early lifting, including high nailing where nails are placed above the manufacturer nailing line, using too few nails, or under-driven or over-driven nails that prevent proper seating. Poor attic ventilation causes heat buildup that warps shingles and weakens adhesive, leading to lifting. Moisture issues such as ice dams can physically push shingles up from below. Physical damage from walking on the roof, fallen branches, or animals can also lift edges. Widespread lifting indicates the roof is near end of life or has systemic ventilation or installation problems and should be inspected by a professional.
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