Asphalt roof shingle cracks.

I inspected this house today. It had 4 layers (yes four). One original from 1923 of wood shingles and three of asphalt. There were a number of vertical cracks in the shingles as shown, however, the grit was in good shape on the shingles. I would guess that they were not more than 8 to 12 years old. No attic access to check for ventilation but small gable vents were visible on each side.

Could these cracks be a manufacturer’s defect? Obviously there would be no warranty claim with four layers.

Would anyone recommend sealing these cracks to squeeze a few more years of life out of the roof surface or should I recommend time for a new roof?


with that many layers it may never leak, but just to be safe, i’d recommend stripping the roof ( that’s ALOT of weight on an old roof) and re-roof before it does leak. adding more matterial now could cause some structural sways and waves that will be even more $$$ to fix.


The type of cracking present is generally indicative of a manufacturing defect.

However, 3 layers of asphalt over wood shake may negate any applicable warranty. The weight of the roofing may also exceed the recommended allowance accounting for expected snow loads.

This area is 2 layers Max with the snow load allowance. I do not see how Massachusetts could be any different.

I would recommend further review along with obtaining estimations for Roof Stripping / Sheathing and Replacement at this time.