Your roof’s underlayment materials are often overlooked. Nonetheless, they’re still a vital component of your home’s roofing system. Underlayment is applied directly atop the roof deck and beneath your preferred roofing materials. Your choice of underlayment is essential because it protects your roof from moisture intrusion and plays a substantial role in how long it lasts.
The two main types of underlayment are synthetic and felt. Synthetic underlayment is typically made from polypropylene or polyethylene. These materials are highly durable and water resistant. They’re also lightweight. Felt underlayment, which consists of asphalt-saturated paper or fiberglass, is more affordable. But it can be less durable and more prone to tearing and falling apart. Here are nine tips to will help you decide between synthetic and felt underlayment for your next roof.
1. Cost
When choosing between synthetic and felt roofing underlayment, cost is almost always the first and most important factor. Felt underlayment is generally less expensive. However, it may not offer the same long-term value as a synthetic material that costs more up-front but has a longer lifespan. In the end, the added durability may save you money on future repairs or a premature replacement.
Parts of Georgia and South Carolina are prone to heavy, tropical-like rains in summer. Therefore, investing in a higher-quality synthetic underlayment might be more cost-effective. Ultimately, you’ll have to decide between initial expenses and long-term benefits when assessing these two roofing materials.
2. How Long You’ll Need the Roof
As mentioned, aside from cost, durability is another main factor when evaluating which type of underlayment to use. With this in mind, consider how long you’ll be at your property. Synthetic underlayment can last more than 25 years. If you’re a buyer requesting a new roof as a pre-purchase condition and expect to live in the house for a long time, we suggest stipulating a synthetic underlayment in the contract. It will resist tearing and withstand harsh weather conditions better than felt.
Felt underlayment, on the other hand, typically lasts 15 to 20 years. It can deteriorate faster under intense sun or heavy rain. Roofs in coastal areas with high humidity receive even less protection and require frequent repairs. However, if you’re moving soon and want to avoid the steeper up-front investment, felt underlayment might be the wiser choice.
3. Local Weather Conditions
In the Southeast, where humidity and storms are common, a weather-resistant roof is paramount. Synthetic underlayment is ideal for combating our frequently harsh weather conditions and intense UV rays. They resist cracking and degrade more slowly under intense sunlight.
Felt underlayment can absorb water. This increases the risk of rot and mold, and felt doesn’t hold up as well under direct UV exposure. For homes in our service areas, we generally recommend a synthetic option.
4. Installation Times
Installation times differ between synthetic and felt underlayment. Synthetic underlayment is generally lighter and comes in larger rolls. This makes it quicker and easier for the roofing company to install. If time is of the essence, going with a synthetic solution can speed up the roofing process.
Felt, while less expensive initially, is heavier and comes in smaller rolls. This requires more effort by the installers and potentially drives up your costs.
5. Weight and Thickness
The weight and thickness qualities of your roofing underlayment play a significant role in preserving your roof’s structural integrity. Since synthetic underlayment is generally lighter than felt, it reduces the overall load on your roof.
Being thicker and heavier, felt underlayment materials add considerably more weight to the roof. Of course, this is a concern in older or structurally compromised buildings. If you’re planning to reroof a vintage home, for example, synthetic underlayment won’t place the same stress levels on your structure as felt could.
6. Slip-Resistant Properties
Synthetic underlayment often features nonslip surfaces that make the installation process safer for the installers. The coating offers better traction for roofers working at steep angles or in wet conditions, allowing them to work more efficiently and minimizes the risk of accidents.
Felt underlayment, on the other hand, can be unsafe to walk on while wet. This presents a potential hazard for installers during the rainy season. The anti-slip substances applied to synthetic underlayment protect roofers while streamlining the installation process.
7. Fire Ratings
When considering the type of roofing underlayment to use, verify its fire rating. Synthetic underlayment scores higher on fire resistance because of the polypropylene and polyethylene materials used in the manufacturing process. These products typically meet Class A fire ratings for optimal protection.
Felt underlayment, traditionally made from asphalt-saturated paper, has lower fire resistance. Most often, this material meets only Class C ratings. In some of the more rural parts of our region, wildfires can be a concern. Homeowners living in or near the outlying wooded areas may want to opt for synthetic underlayment.
8. Breathability and Ventilation
Your roof’s breathability and ventilation are essential for protecting attic space. Synthetic underlayment allows moisture to escape while preventing water from entering your home. This helps control humidity levels in your attic. Synthetic underlayment also prevents mold and mildew from growing in this space and creating an unhealthy breathing environment in the rest of your home.
Felt underlayment is known for trapping moisture and is considerably less breathable. This leads to potential rot and mold issues over time. In our humid climates, synthetic underlayment gives you better air circulation and more balanced air in your attic while protecting your roof’s infrastructure.
9. Manufacturer Warranties and Support
Manufacturer warranties and support are major bonuses no matter which underlayment solution you choose. Synthetics, however, tend to include warranties that may last up to 30 years. This reflects the manufacturer’s confidence in their product’s durability and performance. These warranties frequently cover material defects and potential failures, so you can rest easy about your roof.
Felt underlayment is also warrantied, but these commitments tend to be more limited. They usually span 15-20 years, the average expected lifespan of the underlayment, and may offer less comprehensive coverage. While a synthetic underlayment warranty might include both product replacement and labor costs, a warranty on felt might not.
Looking for a Professional Roofing Consultation?
As you can tell, choosing the right roofing underlayment isn’t overly complicated. But many of the above factors are often overlooked. The main takeaway is you’ll get a more lasting solution with a synthetic underlayment. As roofing experts, our team at Fraser Roofing, LLC can guide you through the entire installation process and help you select the right underlayment solution in many parts of Georgia and South Carolina. We’ll also ensure that your new roof meets all the local safety and performance requirements.
Whether you’re dealing with a new construction or replacing an old roof, our team at Fraser Roofing, LLC offers customized roofing solutions for virtually every type of residential roofing structure. We also provide storm damage repairs and gutter replacement services. You can trust our experienced pros for your next roofing project.
Contact us at Fraser Roofing, LLC today to schedule a roofing consultation!
