What would cause this damage?

Found this on an inspection yesterday. it was mostly a hip roof and all faces were equally damaged widespread throughout the roof. Thanks for any input.

Looks like a manufacturers defect.

Hundreds of areas like this random all over the roof.

Just one area like this observed.

that’s what it’s looking like. Unless they laid the shingles cockeyed before installation and adhesive strip tore off the granular surface.

Thanks Reece and Roy, anyone else have any thoughts?

Here’s a similar defect that is a little more pronounced. Are you seeing this, but smaller?


Just the one post photo close to that scale most damage was about the size of a “tootsie roll” in size.

Installers wearing baseball cleats for traction on the roof?

Instead of throwing them off the roof, the installer might have thrown his cut pieces on the new shingles, with the sealant strip facing down. When they went to clean up, the granules came up were they were stuck to the sealant strip.

#1 and #3 are defects similar to blisters where the asphalt layer has separated at the interface with the mat, just like it does with blisters. It appears to be an asphalt quality issue, meaning impurities in the asphalt.
#4 looks like spliced shingles. Spliced shingles are created to keep the production line moving, but are supposed to be thrown out. Given the quality of the asphalt, I guess it’s not surprising that they’re including spliced shingles in their bundles.
In any case the shingles are defective.