roof tech standing on a roof and installing underlayment

Roof underlayment plays a crucial role in protecting your home from water damage and ensuring the longevity of your roofing system. It’s a water-resistant or waterproof barrier material installed directly onto your roof deck before the roofing material, such as shingles, tiles, or metal panels. Choosing the right type of roof underlayment and proper installation is vital to the overall performance of your roof. This article discusses the various types of roof underlayment, including:

  • The 4 types of roof underlayment
  • Choosing the right underlayment
  • 10 installation tips for roof underlayment
  • Additional considerations

👉 4 Types of Roof Underlayment

close up image of a roll of underlayment

Understanding the different types of roof underlayment is essential for making an informed decision about your roofing system. Each type offers unique benefits and considerations, ensuring you can choose the best option for your home’s specific needs.

1. Asphalt-Saturated Felt

Asphalt-saturated felt is one of the oldest and most traditional types of roof underlayment. It is made from a combination of organic or fiberglass base soaked in asphalt. Available in two standard weights, 15-pound and 30-pound, this type is popular for its affordability and ease of installation.


  • Cost-effective
  • Readily available
  • Provides a good barrier against water


  • Can tear easily
  • Less durable compared to synthetic options
  • Can absorb moisture and wrinkle

2. Synthetic Underlayment

Synthetic underlayment is a newer, more advanced option that has gained popularity due to its superior performance characteristics. Made from polypropylene or polyethylene, synthetic underlayment is lightweight, durable, and resistant to tears and UV damage.


  • Highly durable and long-lasting
  • Resistant to tearing and weather damage
  • Lightweight and easy to handle
  • Excellent water resistance
  • Does not absorb moisture


  • More expensive than asphalt-saturated felt
  • Requires careful installation to avoid damage

3. Rubberized Asphalt

Rubberized asphalt underlayment is a premium option that offers superior water resistance and durability. It typically comes with a peel-and-stick backing that makes installation easier and ensures a tight seal around nails and other roof penetrations.


  • Excellent waterproofing capabilities
  • Self-sealing around nails and fasteners
  • Highly durable and long-lasting
  • Resistant to extreme temperatures


  • Higher cost
  • Requires careful installation to ensure proper adhesion

4. Self-Adhered Membranes

Self-adhered membranes are a type of underlayment that includes a sticky backing, allowing them to adhere directly to the roof deck. This provides an added layer of protection against water infiltration.


  • Strong adhesive properties for a secure installation
  • Excellent water resistance
  • Can provide an extra layer of insulation


  • More expensive than traditional options
  • Can be more challenging to install properly

🏠 Choosing the Right Underlayment

roof tech installing roof underlayment

Selecting the appropriate underlayment for your roof depends on several factors, including your climate, the type of roofing material, and your budget. Here are some considerations to help guide your decision:

  • Climate: In regions with heavy rainfall or snowfall, a more durable and water-resistant underlayment, such as synthetic or rubberized asphalt, is advisable. For milder climates, asphalt-saturated felt may suffice.
  • Roofing Material: Certain roofing materials, like metal or tile, may require specific types of underlayment to perform optimally. Always consult the manufacturer’s recommendations.
  • Budget: While synthetic and rubberized asphalt underlayments offer superior performance, they are also more expensive. Weigh the long-term benefits against the initial cost to determine the best option for your budget.
  • Installation Complexity: Some underlayments are easier to install than others. If you’re doing the installation yourself, consider an underlayment that is user-friendly and requires minimal specialized tools or techniques.

💡 10 Installation Tips for Roof Underlayment

Proper installation of roof underlayment is crucial to ensure its effectiveness. Below are some general tips to help you achieve a successful installation:

1. Prepare the Roof Deck

Before installing any underlayment, ensure the roof deck is clean, dry, and free of debris. Remove any old nails, staples, or roofing materials that could damage the underlayment.

2. Install Drip Edge

Begin by installing a drip edge along the eaves and rakes of the roof. The drip edge helps direct water away from the roof and into the gutters, preventing water damage to the roof deck and fascia.

3. Start from the Bottom

Always start installing the underlayment from the bottom edge of the roof and work your way up. This ensures that each subsequent layer overlaps the one below, providing better water protection.

4. Overlap Layers Properly

Overlap each row of underlayment by at least 2 inches horizontally and 6 inches vertically. This helps create a continuous barrier against water infiltration.

5. Secure the Underlayment

Use roofing nails or staples to secure the underlayment to the roof deck. Be sure to follow the manufacturer’s recommendations for spacing and placement of fasteners. For self-adhered membranes, ensure the adhesive is properly activated by pressing the material firmly onto the deck.

6. Pay Attention to Valleys and Penetrations

Valleys, roof penetrations (such as vents and chimneys), and other vulnerable areas require special attention. Use additional layers of underlayment or specialized flashing materials to ensure these areas are well-protected against water infiltration.

7. Install Ice and Water Shield

In colder climates, consider installing an ice and water shield along the eaves, valleys, and around roof penetrations. This self-adhered membrane provides extra protection against ice dams and wind-driven rain.

8. Avoid Wrinkles and Bubbles

Ensure the underlayment lies flat and smooth against the roof deck. Wrinkles and bubbles can create pathways for water to penetrate, compromising the underlayment’s effectiveness.

9. Work Safely

Roof work can be dangerous, so take appropriate safety precautions. Use proper fall protection equipment, work on a stable and dry surface, and avoid working in adverse weather conditions.

10. Follow Manufacturer Guidelines

Always refer to the manufacturer’s installation guidelines for the specific type of underlayment you are using. Each product may have unique requirements and recommendations to ensure optimal performance.

🤨 Additional Considerations

When evaluating roof underlayment options, it’s important to consider additional factors such as ventilation, regular inspections, and installation. These considerations can greatly impact the performance and longevity of your roofing system.

  • Proper Ventilation: Adequate roof ventilation is essential for the longevity and performance of your roofing system. Proper ventilation helps regulate temperature and moisture levels in the attic, preventing issues such as mold growth, wood rot, and ice dams. Ensure your roof has sufficient intake and exhaust vents to promote good airflow.
  • Inspect Regularly: Regular inspections of your roof and underlayment are crucial to catch potential issues early. Look for signs of damage, such as tears, wrinkles, or water stains, and address them promptly to prevent further damage.
  • Professional Installation: While some homeowners may choose to install underlayment themselves, professional installation is often recommended, especially for more complex or premium products like synthetic or rubberized asphalt underlayment. Professional roofers have the experience and tools necessary to ensure a proper and effective installation.

🙌 Secure Your Home’s Future with Expert Roofing Solutions from Secured Roofing and Solar

Choosing the right type of roofing underlayment and ensuring its proper installation are critical steps in protecting your home from water damage and extending the life of your roofing system. At Secured Roofing and Solar, we specialize in this exact process. Whether you opt for traditional asphalt-saturated felt, advanced synthetic underlayment, or premium rubberized asphalt, our team has the expertise to guide you through the benefits and installation requirements of each type. We understand the importance of factors like climate, roofing material, and budget in making the best decision for your home.

With our experienced professionals and a commitment to quality, Secured Roofing and Solar delivers reliable and durable roofing solutions that stand the test of time. Don’t leave your roofing needs to chance—trust the experts who prioritize your home’s protection and longevity.

Contact us today to schedule a consultation and take the first step towards a secure and lasting roof!

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