Cutting Callbacks From This Costly Problem.
Few callbacks are more frustrating than a homeowner pointing out a roof that doesn’t look flat after installation. Buckled shingles can create concerns about workmanship, even when the root cause lies beneath the shingles themselves. Understanding why shingles buckle—and how to prevent it—can help you reduce callbacks, protect your reputation, and deliver better long-term roof performance.
What Causes Shingle Buckling?
Buckling occurs when asphalt shingles become distorted and fail to lie flat. The most common causes are movement in the roof deck and wrinkles in the underlayment. Moisture is often the underlying factor behind both issues.
When roof decking absorbs moisture from rain, dew, or humidity during construction, the wood can expand. As moisture levels change, the decking may move enough to create visible ridges or waves in the shingles above. Underlayment, too, can absorb moisture and wrinkle, telegraphing those imperfections through the finished roof system.
In some cases, improperly spaced roof decking can contribute to buckling as panels expand. Uneven decking surfaces, structural movement, or installation-related issues can also produce distortions that resemble buckling.
Why Ventilation Matters.
One of the most overlooked contributors to buckled shingles is inadequate attic ventilation. When airflow is restricted beneath the roof deck, excess heat and moisture can accumulate in the attic. Over time, this environment can contribute to changes in the moisture content of wood decking, increasing the likelihood of deck movement and shingle distortion. Industry experts consistently identify proper ventilation as a key component in managing both temperature and moisture levels within the attic space. That’s why ventilation should be viewed as more than a code requirement. It is an essential part of a complete roofing system. Balanced intake and exhaust ventilation help maintain airflow from the eaves to the ridge, supporting the long-term performance of both the roof deck and the shingles above it.
Preventing Costly Callbacks.
The good news is that buckling can often be prevented through proper installation practices:
- Keep decking materials dry before installation.
- Inspect decking for proper spacing and condition.
- Install underlayment smoothly and avoid trapping moisture within the system.
- Ensure attic ventilation meets building code and manufacturer requirements.
- Verify that airflow pathways remain open from intake vents to exhaust vents.
The Bottom Line.
It’s important to remember that when buckled shingles appear, the shingles themselves are often not the problem. Moisture management, deck conditions, underlayment installation, and ventilation all play critical roles in roof performance. Don’t skimp on materials and don’t shortcut proper installation. In the long run, you’ll save on callbacks and save your reputation. To learn more about quality ventilation and underlayment solutions that can help prevent shingle buckling, visit MarcoIndustries.com. To contact us directly, email or call 1-800-800-8590.