Some loose granules after installation are excess material rather than proof of a defective roof. GAF explains why initial shedding can occur
GAF technical bulletin: Granule loss on new shingles.
What this means for your roof
Some loose granules after installation are excess material rather than proof of a defective roof. GAF explains why initial shedding can occur. Continuing heavy loss, exposed asphalt or localized damage deserves a closer inspection.
A useful question for your contractor
Ask for photos of the shingle surface rather than judging the roof from gutter debris alone.
Ask for the answer to be tied to the actual roof condition and the exact product being installed. Keep the agreed repair or installation detail with your estimate and project photos.
Bulletin revision: February 1, 2021. This is the date of the manufacturer source, not a claim that this website guide existed on that date.
Read GAF: Granule loss on new shingles
This homeowner summary explains the cited bulletin. The complete manufacturer document and current product instructions govern the installation details. A requirement for one manufacturer or product should not be transferred to another without checking.