Shingle Damage Evaluation – Other Damages That May Be Mistaken for Hail Damage – Part 6b

Posted by in Shingles | July 30, 2012

This post is Part 6b of Shingle Damage Evaluation and follows Other Damages That May Be Mistaken for Hail Damage – Part 6a.

Other Damages That May Be Mistaken For Hail Damage – Part 6, is comprised of four posts that discuss the causes and characteristics of damages that are commonly inflicted on shingles by other means, such as human or animal activities.  These are other damages may be mistaken for hail damage by someone poorly trained and/or the inadequately inexperienced.

Following is the second list of three damages effected by other means:

  1. Granule Cover And Asphalt Coating Loss  – A loss of granule cover and asphalt coating with defined edges and a defined shape, such as a line matching the width of the shingle sealant, are due to pulling off the granules and the asphalt during the removal of an object that had adhered to the surface of the shingle.  The unwanted adhesion is commonly due to a missing slip sheet at the sealant strip, the inadvertent application of some adhesive material prior to packaging or storage, or the inadvertent sticking of shingles temporarily placed on the new roof surface during installation.  These are distinguished from hail impact damage by their shape and the lack of being accompanied by a fracture, an indentation, and/or a soft area in the shingle mat.

  1. Lichens – Lichens are biological growths that consume the asphalt material of the shingle.  They are more common on shaded and slow drying areas of the roof.  When the lichens are washed away by heavy rain, pressure washing, foot traffic, wind, etc. the granules previously covered by the lichen are often dislodged leaving a somewhat circular area of granule loss.  Lichen damage is often mistaken for hail damage due to its circular shape.  Lichen damage is not accompanied by a fracture, an indentation, and/or a soft area in the shingle mat or an impression in the asphalt, but often may be identified by remnants of the lichen growth even after the shingles have been cleaned.  Areas of roof with lichen growth are often shielded from direct impact by hail stones as they are often located under trees, overhangs, and other shadow casting objects.


lichens on shingles

SDE-44 Lichen growth on shingle.

  1. Marring – Marring is a sunken impression and/or mounding of the asphalt and granules in the shingle surface.  Marring is not accompanied by an indentation or fracture in the shingle mat.  Marring is due to foot traffic and/or the placement of tools on the shingles when the shingles became hot, soft, and pliable by the heat of ambient temperatures and/or the sunlight.  Marring is more common on steep slopes where more friction forces are inadvertently applied to avoid sliding off the roof.  Marring is distinguished from hail impact damage by the mound of “plowed” granules.



SDE-45 Marring in shingle surface.


The next post will discuss additional damages and anomalies that are often mistaken for hail damage.