Intentional Damage? Or Something Else?
Not all shingle tabs that are creased or unsealed by hand lifting are done so with intention to damage. During the replacement or repair of shingles, flashings, or other roof component, shingle tabs are often lifted and bent back to drive nails through the underlying shingle or other roofing component. On occasion the roofer forgets to re-seal the unsealed tabs or to replace the damaged ones.
What to look for:
- Diagonal creasing in tab allows access to location of nail for underlying shingle strip,
- Underlying shingle strip has been re-nailed as evidenced by double nailing or cleaner nail heads,
- Creased or unsealed shingles are along an area of newer looking roof components (shingles, flashings, boots, etc.),
- There are reports of previous roof repairs,
- The fracture in the tab seal strip is in usually in the asphalt sealant and does not extent into the shingle mat material due to the more careful lifting and unsealing of the tabs,
- The asphalt sealant strip is discolored from having been unsealed for an extended period of time,
- Other tabs exhibit re-sealing with hand applied asphalt sealant, or
- The pattern of unsealed tabs matches a pattern of repair work.
You get the general idea: look for roof construction details that are not consistent with a one-time installation of the roof components , but are indicative of intentional alterations that improve the roof construction.