What does granule loss on shingles mean?
By Best Roofing Answers · Published May 2026 · Updated July 2026
Granule loss is the shedding of the mineral coating that protects the asphalt mat from UV; a light amount is normal in the first year after install, but field-wide bald spots, granules piling in gutters, or exposed black mat generally indicate the shingles are past their functional lifespan or were hail-damaged.
Normal shed vs failure signal
Per HAAG Engineering forensic standards, mineral granules serve two functions: UV shielding and fire resistance (ASTM D3462 Class A). Loss of granules exposes the asphalt to UV; once the mat is exposed, deterioration accelerates rapidly — commonly 12–24 months to visible cracking.
Fresh circular granule loss with a soft, bruised mat under it is the HAAG-standard signature of hail damage and is worth an insurance-claim inspection, especially after a storm event confirmed by NOAA SPC data.
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