Have you seen bumpy surfaces or tiny bubbles appearing on
your roof shingles? That’s a sign of blistering, a widespread
roofing problem many Calgary homeowners encounter. While
it may not seem serious at first, blistering can weaken your
shingles and lead to long-term roof damage. At Straight Path
Construction, we help homeowners understand the causes of
roof problems so they can take action early. Let’s explore why
asphalt shingles blister and what you can do about it.
What Is Shingle Blistering?
Blistering occurs when there are tiny bubbles or pockmarks on
the asphalt shingle surface. Blistering appears as raised spots and
will, over time, rupture, leaving behind exposed patches.
This leaves the shingle exposed to sunlight and weather, which
accelerates its aging and loss of protective ability. Blistering, if
not cured, reduces the lifespan of your roof and builds
up the potential for leaks.
Moisture Trapped During Manufacturing
The most frequent cause of blistering is moisture trapped within
the shingles while being manufactured. Under the influence of
sunlight, the entrapped moisture warms up and exerts pressure
under the shingle surface. The pressure builds bubbles that
develop as blisters. Although not all blisters are necessarily
damaging, they wear away the protective granules and
shorten the life of the shingle.
Poor Roof Ventilation
A hot, poorly ventilated attic can also blister shingles. When there
is no airflow, heat and humidity accumulate under the roof,
overheating the shingles. This intense heat from underneath
plus sunlight from above can push air or moisture out of the
shingles, creating blisters. Adequate attic ventilation keeps this
interior heat down and lengthens your roof’s lifespan. Straight
Path Construction provides attic inspections to enhance
your home’s ventilation system.
Installation Mistakes
Improper installation can also lead to blistering. If shingles are
installed over a damp roof deck or during very hot weather, the
trapped heat and moisture can trigger blisters. Using the wrong
nails, skipping underlayment, or working in poor conditions can
also create long-term problems. That’s why it’s important to
work with trusted, professional contractors like Straight Path
Construction, who follow proper installation standards every time.
Effects of Blistering on Your Roof
Blisters are small but can lead to big issues if they rupture.
Once the surface layer of the shingle ruptures, it allows the
sun and rain to reach the asphalt below. This will cause weakening
of the shingle, and it will crack, curl, or break more easily. A
roof with a lot of blisters might have to be repaired more often
or in some instances, replaced sooner.
Final Thoughts
Blistering is more than a cosmetic concern; it’s a sign that your
roof requires attention. Whether the cause is heat, moisture,
or inadequate ventilation, it’s best that blistered shingles
be professionally inspected. At Straight Path Construction,
we provide free inspections and frank counsel to maintain your
roof intact and your house secure.
Contact us now
Notice blistered shingles on your roof?
Contact Straight Path Construction or go to our website to
arrange your complimentary roof inspection in Calgary. We’ll locate
the problem and assist you in repairing it the proper way.
Frequently Asked Questions (FAQs)
How does blistering on asphalt shingles appear?
Blistering can be seen as bubbles or bumps protruding from
the surface of the shingles. Eventually, the bubbles might burst
and create small pits or areas of exposed shingle where
granules have eroded.
Is blistering a significant roofing issue?
Blistering can become severe if neglected. When blisters break
open, they subject the shingle to sunlight and water, which
accelerates aging and may result in cracking leaks, or
premature roof failure.
What are the causes of blistering on roof shingles?
The most frequent reasons are moisture getting in during
manufacturing, inadequate attic ventilation, and improper
installation techniques. Each of these can lead to heat and pressure
accumulation underneath the shingles.
Can blistered shingles be repaired?
Small areas of blistering may not necessarily need immediate
repair, but if blisters rupture or extend over large areas, it’s best
to have them inspected. Replacing them may be necessary in extreme cases.
Does Straight Path Construction repair blistered roofs?1
Yes! We provide complimentary roof inspections in Calgary and
perform repairs or replacements depending on the condition
of your roof. We also assist in repairing attic ventilation problems
to avoid future blistering.
