Blistering on New Roof Shingles: Causes & Solutions

Written By Kevin Kabaria

Did you know that over 75% of homeowners experience issues with blistering on new roof shingles within just five years of installation? (source: Roofing Industry Magazine). This alarming statistic highlights a common problem that can affect the appearance, efficiency, and longevity of your roof. As a homeowner, understanding the causes of blistering is crucial because it can lead to costly repairs and even reduce the value of your home if left unchecked. In this blog post, we'll explore the underlying factors contributing to shingle blistering, provide insights into how you can prevent it, and share practical advice for addressing this issue effectively.

Blistering is more than just a cosmetic concern; it can signify deeper structural problems that compromise your roof's integrity. By learning about the causes and solutions, you'll be equipped to maintain your roof's health and protect your investment. Whether you're dealing with new roof installation or maintaining an existing one, this guide will empower you with the knowledge to make informed decisions and safeguard your home from potential damage.

In the following sections, we'll delve into the materials and manufacturing processes that can lead to blistering, discuss environmental factors that exacerbate the problem, and provide actionable tips to prevent and repair blistering issues. By the end of this post, you'll have a comprehensive understanding of how to keep your roof in optimal condition, ensuring it remains a strong, protective barrier for years to come.

Table of Contents

Introduction to Blistering on New Roof Shingles

Overview of the Problem

Blistering on new roof shingles is a common problem for homeowners. It occurs when air, gas, or moisture becomes trapped inside the shingles, creating bubbles that resemble air pockets under a sticker. These blisters often appear in asphalt shingles, causing them to lose adhesion to the underlayment and roof decking, which results in pockets where moisture and air infiltrate. Learn more about roof maintenance.

Warning: Blistering can lead to significant roof damage if not addressed early. Consider scheduling a roof assessment to identify potential issues.

What are "Rash Blisters"?

These blisters are sometimes called "rash blisters." While some manufacturers consider them cosmetic, blisters can shorten the shingle's lifespan. The raised areas wear down more quickly due to weather exposure, potentially leading to the need for a new roof sooner.

Why Does Blistering Happen?

Blistering can result from various factors, including the type of asphalt, weather conditions, or installation errors. Moisture trapped within the shingle during manufacturing or installation is a significant cause. When heated by the sun, this moisture expands, forming blisters. Contrary to some beliefs, foam insulation contacting hot asphalt is unlikely a cause. Get Your Roof Assessment to identify potential issues early.

Importance of Addressing Blistering

Addressing blistering on new shingles is crucial as they can lead to significant roof damage. Blisters expose the lower layers to elements like rain, wind, and sun, potentially causing leaks and accelerating wear. Exposed decking can rot, and the underlayment can suffer damage, marking blisters as weak spots on your roof.

Potential Damage from Blisters

  • Water leaks
  • Rotting of roof decking
  • Damage to underlayment

Prevention Tips

  • Regular inspections
  • Prompt repairs of affected areas
  • Ensure proper ventilation

Long-Term Damage from Blisters

Ignoring blisters can escalate into substantial problems, necessitating costly repairs or even a complete roof replacement. Industry data indicates claims for extensive blistered shingles, sometimes covering up to 40 squares (4000 square feet), have been settled. An example involves Vista® shingles, where manufacturers often require shingle samples before authorizing repairs.

Energy Efficiency and Home Value

Repairing blisters enhances energy efficiency and maintains your home's value. Blisters can compromise your roof's insulation, increasing energy bills as heating and cooling systems work harder. A well-maintained roof boosts your home's appearance and value, while a damaged one can diminish it. Fixing blisters safeguards both functionality and value.

Understanding Roof Shingle Composition

Roof shingles dominate the residential roofing market, covering approximately 60% due to their durability, cost-effectiveness, and aesthetic appeal. Understanding shingle composition is vital for homeowners and contractors as it significantly impacts roof longevity and performance. For instance, understanding asphalt's waterproofing role aids in diagnosing leaks and selecting appropriate repair methods. This section details the materials used in shingle manufacturing and explores common shingle types.

Materials Used in Shingle Manufacturing

  • Asphalt
  • Fiberglass
  • Mineral Granules

Common Types of Shingles

  • Asphalt Shingles
  • Wood Shingles
  • Metal Shingles

Materials Used in Shingle Manufacturing

Shingles typically consist of asphalt, fiberglass, and mineral granules, each serving a crucial role.

Asphalt

Asphalt acts as the primary waterproofing agent, protecting against rain and moisture. It functions as a flexible sealant, forming a barrier against water penetration. Often, it's combined with other materials to enhance durability and flexibility.

Fiberglass

Fiberglass provides structural support and increases fire resistance. This mat acts as a skeleton within the shingle, offering a base for asphalt and preventing tearing and cracking.

Mineral Granules

Mineral granules coat the shingle's surface, serving multiple purposes:

  • They protect against UV rays, which can cause premature aging.
  • They provide color options, like gray, brown, or green.
  • They offer additional fire resistance.

The combination of these materials results in a robust and visually appealing product. Consider getting a roof assessment to evaluate the condition of your shingles.

Common Types of Shingles

Several shingle types exist, each with unique characteristics and benefits.

Asphalt Shingles

Asphalt shingles are the most common, known for affordability and ease of installation, contributing to their residential market popularity. Their lightweight and manageable size simplify installation. They come in two main varieties:

  • Three-Tab Shingles: Lightweight and cost-effective, making them popular for budget-conscious homeowners.
  • Architectural Shingles: Thicker, more durable, and offer a textured appearance, often with longer warranties due to their expected lifespan. Learn more about roof maintenance to extend the life of your asphalt shingles.

Wood Shingles

Typically made from cedar, wood shingles offer a natural aesthetic but require more maintenance than asphalt shingles, including regular treatments for rot and insect resistance, often recommended annually or biannually.

Metal Shingles

Metal shingles are gaining popularity for their longevity and energy efficiency, though they are typically more expensive. However, they offer long-term cost savings due to durability and potential energy savings. Choosing the right shingle type depends on individual needs, budget, local climate, and desired lifespan.

Causes of Blistering in New Roof Shingles

Blistering on new roof shingles detracts from your home's appearance and may indicate deeper problems. Understanding the causes of shingle blistering helps address the issue and prevent future occurrences. Several factors contribute to this problem, impacting the lifespan and performance of your roof. Knowing these causes empowers homeowners to take preventive measures and protect their roofing investment. Consider getting a professional roof assessment to identify potential issues early.

Main Causes of Blistering

  • Moisture Entrapment
  • Manufacturing Defects
  • Installation Errors
  • Inadequate Attic Ventilation

Moisture Entrapment

Moisture trapped within shingle layers is a primary cause of blistering. When moisture gets between the shingle's membrane and the substrate (the underlying roof deck), it forms pockets. These pockets expand in the sun's heat, creating blisters. Trapped moisture often stems from inadequate drying during manufacturing or improper installation on a damp roof deck. Moisture-laden shingles can shorten roof lifespan as heating and cooling cycles worsen the blistering. Homeowners can mitigate this by ensuring proper installation and choosing high-quality shingles from reputable manufacturers. For more information on maintaining your roof, learn more about roof maintenance.

Manufacturing Defects

Manufacturing defects are another significant contributor to shingle blistering. Poor manufacturing processes can trap gases or moisture within the shingle, causing blisters. Some manufacturers refer to these as "rash blisters," indicating a shorter shingle lifespan. Defective shingles may not adhere correctly to the underlayment (the protective layer between shingles and the roof deck). This creates air pockets and an uneven roof surface, promoting blister formation. While manufacturer warranties often cover repairs or replacements for defects, the inconvenience and potential damage remain. Documented cases show blistering and cracking long before warranties expire. For example, shingles might blister in a few years despite having a 20-year warranty. Choosing shingles from manufacturers known for quality control is essential.

Installation Errors

Improper installation contributes to shingle blistering. Inadequate sealing around vents, chimneys, or other roof penetrations, along with incorrect shingle placement, can trap air and moisture, leading to blisters. Using the wrong roofing materials or tools can also compromise shingle integrity, increasing blister susceptibility. Hiring experienced, certified roofing contractors minimizes installation errors. Regular roof inspections and maintenance can identify potential problems early.

Inadequate Attic Ventilation

Poor attic ventilation is often overlooked as a cause of shingle blistering. Proper ventilation allows heat and moisture to escape the attic, protecting roofing materials. Insufficient ventilation causes heat and moisture buildup, leading to premature shingle blistering and deterioration. This is especially true in areas with extreme temperature swings. According to industry experts, many homes in Colorado, for example, have inadequate attic ventilation, resulting in frequent blistering and granule loss. Homeowners should consult roofing professionals to assess and recommend appropriate ventilation solutions like soffit vents, ridge vents, or powered attic ventilators. While the effectiveness of some ventilation methods has been debated, proper attic ventilation remains a crucial consideration.

Environmental Factors Contributing to Blistering

Roof shingle blistering is a common problem. Understanding why it happens can help you prevent it. Several environmental factors contribute to blistering, including temperature changes, humidity, and sun exposure. Knowing about these factors can help you protect your roof and make it last longer.

Environmental Factors

  • Temperature Fluctuations
  • Humidity Levels
  • Sun Exposure

Temperature Fluctuations

Temperature changes are a major cause of roof shingle blisters. During the day, the sun's heat makes asphalt shingles expand. This expansion can trap air and moisture, forming blisters. At night, temperatures drop, and the shingles contract. This constant expanding and contracting weakens the shingles over time, leading to potential cracking, curling, and even broken shingles. If you live in an area with big temperature swings, consider using shingles designed for those conditions.

Effects of Expansion and Contraction

The repeated expansion and contraction from temperature changes can damage the shingles, shortening the lifespan of your roof. Regular roof inspections can help identify early signs of damage from temperature fluctuations. Consider scheduling a Get Your Roof Assessment to identify potential issues early on.

Humidity Levels

High humidity also contributes to shingle blistering. Humidity increases the amount of moisture trapped under the shingles. This moisture, combined with heat, creates blisters. Poor attic ventilation exacerbates the problem, as the trapped moisture has nowhere to go, much like a pressure cooker. Industry data shows that about 70% of homes don't have enough attic ventilation. Good attic ventilation and moisture-resistant materials can help prevent moisture buildup. Synthetic underlayment can act as a barrier against moisture. Blistering can expose your roof to the elements, leading to leaks and premature roof failure. To learn more about roof maintenance, visit our website.

Sun Exposure

Direct sunlight also causes shingle blistering. The sun's heat increases the temperature of the roof, making the trapped air and moisture expand even more, especially in areas with abundant sunshine. Reflective roofing materials or shade structures can help reduce the sun's impact. Reflective materials bounce sunlight away, keeping the roof cooler. Trees or awnings can provide shade. Regular roof inspections can help you find blisters early. Small, raised areas on the shingles are a sign of blistering. Blisters are usually caused by trapped moisture or poor ventilation. By understanding and addressing these environmental factors, you can protect your roof from blistering. Choosing the right materials, ensuring good ventilation, and performing regular maintenance can help your roof last longer and prevent costly repairs.

Identifying Blistering on Roof Shingles

Understanding the signs of roof shingle blistering is crucial for homeowners. Identifying blistering early can prevent further damage and maintain your roof investment. This section explains how to recognize blistering, spot early warning signs, and distinguish blisters from other roof problems. You can take timely action and protect your roof's integrity by learning these key indicators.

Signs of Blistering

  • Raised areas or bubbles on shingles
  • Visible granule loss
  • Increased energy bills

Visual Signs of Blistering

Roof blisters appear as raised areas or bubbles on the shingle surface. These blisters range in size, from small bumps to large, noticeable protrusions, disrupting the shingle's smooth appearance. Blisters form when trapped gas, air, or moisture expands under the shingles with the sun's heat. This expansion causes the shingles to lose adhesion with the underlying roof deck and underlayment. The resulting separation creates voids, similar to those found in built-up roof membranes. Often, blisters break open, exposing the underlying asphalt and leading to granule loss. This loss weakens the shingle's weather resistance, increasing susceptibility to sun and rain damage. Regularly inspect your roof, especially after storms, for new or worsening blisters.

Early Warning Indicators

Before blisters become visually obvious, there are early warning signs. One key indicator is excess moisture or heat in the attic. Inadequate attic ventilation traps heat and moisture, creating ideal blistering conditions. Industry data suggests inadequate attic ventilation is a significant contributor to blister formation in Colorado, often leading to granule loss. Another indicator is a rise in energy bills due to trapped heat affecting temperature regulation. This trapped heat can also contribute to premature shingle aging. Addressing these subtle signs early, such as improving ventilation, can prevent more serious roof problems. Learn more about roof maintenance.

Differentiating Blisters from Other Issues

Blistering is often confused with hail damage or shingle delamination. Hail damage typically appears as indentations or punctures with granule loss in a distinct pattern. Unlike the raised bumps of blisters, hail damage resembles the marks left by a ball peen hammer, often scattered randomly across the roof. Shingle delamination, where shingle layers separate, can also resemble blistering due to its raised appearance. However, delamination shows peeling or flaking, unlike the bubble-like blisters. Delamination is a structural problem within the shingle itself. While some manufacturers consider blisters a cosmetic defect ("rash blisters"), others see them as a sign of reduced shingle lifespan. Similarly, blisters in built-up roof membranes are also viewed as problematic. To ensure accurate identification, consult a roofing professional. They can differentiate between these issues and recommend appropriate solutions. This accurate diagnosis helps you choose the right action, from improving ventilation to replacing damaged shingles. Consider a Get Your Roof Assessment for a professional evaluation.

Preventing Blistering in New Roof Shingles

Blistering on new roof shingles is a preventable problem that can lead to costly repairs. Understanding the causes of blistering, such as trapped moisture, air, or gas, allows homeowners to take proactive steps to protect their roofs. This section explores key prevention strategies, including proper installation, quality material selection, ventilation, and regional climate considerations. By addressing these factors, you can extend the life of your roof and avoid the frustration of premature shingle failure. Consider a Get Your Roof Assessment to identify potential vulnerabilities and ensure optimal roof health.

Prevention Strategies

  • Proper Installation Techniques
  • Choosing Quality Materials
  • Ensuring Adequate Ventilation
  • Considering Regional Climate

Best Practices for Installation

Proper installation is the first line of defense against shingle blistering. A clean, dry roof deck is essential before shingle installation begins. This prevents trapped moisture, a common cause of blisters. High-quality, compatible adhesive strengthens the bond between shingles and the underlayment, preventing pockets where moisture and air can accumulate. Following manufacturer guidelines for nail placement and quantity is also crucial. Incorrect nailing compromises the shingle's seal, allowing moisture entry and increasing blister risk.

Choosing Quality Materials

Choosing quality materials plays a vital role in preventing shingle blistering. Select shingles with proper ventilation features and a high softening point bitumen mix. Bitumen, a key component in asphalt shingles, is less prone to softening and losing adhesion under high temperatures with a higher softening point. High-quality shingles better withstand environmental stressors and maintain their structure, preventing layer separation and blister formation. Look for shingles with proven durability and comprehensive warranties. Investing in quality materials upfront can save you money on future repairs or replacements caused by blistering.

Importance of Proper Ventilation

Proper ventilation is essential for preventing moisture and heat buildup, two primary contributors to shingle blistering. Trapped heat softens asphalt, increasing blister susceptibility, while excess moisture creates pressure that leads to bubble formation. Effective attic ventilation regulates temperature and humidity, mitigating these risks. Industry data suggests that roughly 70% of homes have inadequate ventilation, putting them at higher risk for issues like shingle blistering. Ensure your roof has sufficient intake and exhaust vents to promote optimal airflow. Regular vent inspection and maintenance, such as clearing clogs that restrict airflow and trap moisture, are crucial for preventing blister formation. According to industry experts in Colorado, inadequate attic ventilation is a leading cause of blistering and granule loss, a related shingle problem. Learn more about roof maintenance to understand the importance of proper ventilation.

Regional Considerations and Climate Impact

Climate significantly influences the likelihood of shingle blistering. In cold climates, proper insulation and ventilation of compact roof/ceiling assemblies are crucial for preventing moisture buildup and blistering. Retrofitting these assemblies with blown-in dense-pack cellulose insulation is a common practice to improve insulation and moisture management. In hot, humid climates, shingles with a high softening point bitumen are essential for withstanding these conditions and reducing blister risk. These shingles often offer enhanced moisture resistance. Consult local roofing professionals familiar with regional climate conditions for recommendations on the best materials and installation techniques. Tailoring your roofing approach to the local climate minimizes blister risk and ensures a longer-lasting, more resilient roof.

Repair and Maintenance Solutions

Homeowners often find blistering on new roof shingles concerning. It impacts a roof's appearance and can cause structural problems if ignored. This section explores short-term and long-term repair options, discusses costs, and advises when to consult a professional. This information helps homeowners make informed decisions to maintain their roofs.

Repair Options

  • Short-term Fixes
  • Long-term Solutions
  • Consulting Professionals

Cost Implications of Repairs

Repair costs for blistered shingles vary depending on the damage and the chosen solution. Short-term fixes like sealant or replacing a few shingles can cost between $150 and $1,830, with the average roof shingle repair costing around $950. Factors like roof size and accessibility influence the final price. Comprehensive repairs like full roof replacements range from $5,000 to $10,000 or more, depending on the roof's size and complexity. Weigh the benefits of each option against the costs. Some warranties cover specific repairs for manufacturing defects, reducing homeowner expenses. Document the issue, keep damaged shingle samples, and contact the manufacturer for potential warranty coverage before starting repairs. Learn more about roof maintenance to understand potential costs and warranty coverage.

When to Consult a Professional

Knowing when to consult a professional is crucial for your roof's health. Seek expert advice if you notice extensive blistering (affecting more than a single square – 100 square feet – of shingles), water leaks, or if problems persist after short-term fixes. Professionals thoroughly assess the roof and recommend the best course of action. They possess the experience and tools for complex repairs, ensuring safety and efficiency. Furthermore, they can help navigate warranty claims, preventing complications. Early professional intervention often prevents minor issues from becoming major problems.

Short-Term Fixes

Short-term fixes offer immediate solutions for blistered shingles, minimizing further damage at a lower cost. Applying roof sealant to affected areas is a common quick fix. This temporarily patches small blisters and prevents water from entering the underlayment. Replacing only the damaged shingles is another cost-effective option, especially if the damage is limited. However, these solutions are temporary and may not address the root cause of the blistering. For example, poor attic ventilation can cause recurring blisters even after patching or replacing shingles because the underlying heat buildup remains.

Long-Term Repair Options

Long-term solutions provide more permanent fixes for blistered shingles, although they require more extensive work. If blistering is widespread or shingles are nearing the end of their lifespan, a full roof replacement might be necessary. Improving attic ventilation is another long-term strategy. This prevents excessive heat buildup, a common cause of blistering. This could involve installing additional vents or ridge vents to help the attic regulate its temperature and reduce stress on shingles. Upgrading to higher-quality shingles with better warranty coverage can also be a worthwhile investment. Longer warranties, sometimes lasting decades, offer greater protection against manufacturing defects and provide peace of mind. While these options have a higher upfront cost, they can save money and trouble over time. Consider scheduling a Get Your Roof Assessment to determine the best long-term solution for your needs.

Conclusion

Blistering on new roof shingles is a common issue that can lead to significant problems if not addressed early. The causes of blistering are multifaceted, often involving the properties of the asphalt, such as its softening point, the presence of moisture, and the effectiveness of attic ventilation. Understanding these factors is crucial for homeowners and roofing professionals to mitigate potential damage and ensure roof longevity. Consider scheduling a Get Your Roof Assessment to identify potential issues early.

Importance of Early Detection and Prevention

Early detection of blistering is key to preventing costly repairs and property damage. Identifying blisters early allows for timely intervention. This might include improving attic ventilation or choosing roofing materials with higher softening points. While the benefits of attic ventilation have been debated, it can still play a role in regulating temperature and moisture, which are contributing factors to blister formation. Using asphalt with a higher softening point makes it less likely to soften and blister under high temperatures. Regular roof inspections are crucial for spotting early signs of blistering, such as small, raised bubbles on the shingle surface. By understanding these signs and the causes of blistering, homeowners can take preventive steps. These steps could include ensuring proper installation and selecting high-quality materials from reputable manufacturers and experienced installers. Learn more about roof maintenance to protect your investment.

Long-term Benefits of Addressing Blistering

Addressing blistering promptly offers several long-term benefits. It extends the lifespan of the roof, enhancing its overall durability and performance. Preventing blisters avoids potential leaks and structural damage, ensuring the roof remains a protective barrier against the elements. Unaddressed blistering can lead to ruptured blisters, exposing the roof deck to moisture, and potentially causing rot, leaks, and expensive repairs. Investing in preventive measures, such as selecting more durable shingle materials, can lead to long-term cost savings by reducing the need for frequent repairs or replacements. According to industry data, neglecting issues like granule loss, which can be exacerbated by blistering, can significantly reduce shingle lifespan and increase vulnerability to weather damage. This reinforces the importance of addressing blistering early to preserve the roof's appearance and protect the property. While some manufacturers consider blistering a cosmetic defect, it can be an indicator of reduced shingle life and should not be ignored.

Additional Resources

This section provides helpful resources for homeowners and professionals to better understand roof shingle blistering. These resources offer insights into the causes, effects, and potential solutions for this common roofing issue. Learning more about blistering helps you make informed decisions about roof maintenance and repairs.

Further Reading

Dive deeper into the topic of roof shingle blistering with these articles and studies.

  • Cash & Kan's scientific study explores the reasons why asphalt shingles blister, focusing on the materials used in shingles and how they react to various conditions.
  • An article from Roofing Industry Magazine explains shingle warranties and what they cover regarding blistering. Understanding your warranty can help you avoid unexpected costs and know the steps to take if blistering occurs. For example, knowing if your warranty covers blister repair or replacement can save you time and money.
  • The Colorado Roofing Contractors Association highlights the importance of proper attic ventilation. According to the association, good ventilation can increase shingle lifespan by up to 24%. This extended lifespan is due to reduced heat and moisture buildup, which are common causes of blistering and granule loss. Roofing contractors have documented numerous issues related to poor ventilation and its impact on how long shingles last.
  • A real-world example shows how understanding warranty coverage is key. A claim for roughly 400 square feet (40 squares) of Vista® shingles was successfully resolved due to blistering. This example demonstrates that claims related to blistering are often successful if you understand your warranty and the claims process. Providing samples of the damaged shingles may be necessary when filing a claim.
  • Inadequate attic ventilation is a frequent cause of blistering, especially in Colorado. This problem leads to trapped heat and moisture, damaging the shingles and potentially causing blisters. Learn more about roof maintenance to understand how proper ventilation can protect your roof. You can also Get Your Roof Assessment to identify potential ventilation issues.

Professional Associations and Guides

Professional organizations offer valuable guidance and support regarding roof maintenance.

  • The National Roofing Contractors Association (NRCA) provides information on proper roofing installation and maintenance, including advice on preventing blistering. Their resources are helpful for both homeowners and professionals. These resources may include best practices for ventilation, shingle selection, and installation techniques.
  • The Asphalt Roofing Manufacturers Association (ARMA) offers detailed resources on asphalt shingles and common problems like blistering. Understanding the properties of asphalt and how blistering occurs are topics likely covered by ARMA. ARMA's guidelines help explain the technical aspects of shingles and how to improve their lifespan. This includes information on how shingles react to weather and choosing the right type for your climate.
  • Staying connected with these organizations gives you access to the latest advancements and best practices in roofing. This knowledge can help you avoid future issues like blistering and maintain a high-quality roofing system.

Disclaimer: This blog post is intended for informational purposes only and should not be considered professional roofing advice. Always consult with qualified roofing contractors and insurance professionals for specific guidance regarding your individual circumstances.

Kevin Kabaria
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