The protective granular surface of shingles wears off as the
asphalt, into which the granules are embedded, begins to harden
over time. Bare spots are often accompanied by fine fissures
on the shingles' surface and by the accumulation of granules
in the gutters.
Buckling is a visible distortion or waviness in the horizontal
lines of shingles, and usually runs in a straight line up
the roof slope. Shingle tabs become exposed to wind and can
be torn off. Very often, the problem is warping in the roof
deck caused by poor attic ventilation. The use of thinner-than-recommended
plywoods and other non-plywood materials adds to the problem.
The upward curling of shingle tabs makes them highly susceptible
to wind and ice damage. This is a problem on older roofs where
moisture build-up in the attic affects the underside of the
Many problems occur at the flashings around vents, soil stacks,
chimneys and vertical wall joints. Is the flashing cracked?
Is the caulking around the flashing dried out? Are the shingles
that lie over the flashing in good shape?
Damage can be caused by extreme wind conditions and snow removal.
Since shingles are supposed to shed water, broken, torn or
missing tabs become obvious entry points for water, especially
on low slope roofs where run-off is slower and at the peaks
of the roof where shingles are the most vulnerable to high
This is the curling under of the shingle tab's bottom edge
and is part of the normal aging process of shingles. The bulge
created is susceptible to substantial damage by wind action,
hail and ice.
DAMMING & VENTILATION
There are other conditions which can affect your roof, such
as ice damming and ventilation. This pamplet covers those
topics as well as other useful information to assist you in
understanding the issues about your roof.