Synthetic or Asphalt Felt?

RRG Roofing presents you with which underlayment is best: synthetic or asphalt felt. Roof underlayment is not precisely something that springs to mind when people think of getting a new roof. But, when it comes time to replace your home’s roof, knowing the distinctions between synthetic underlayment and roof felt paper is critical.


If you are going to spend that much money on a new roof, you want to be sure it is done well. Do you want to extend the life of your roof? To do so, it is important to think about and choose the ideal underlayment for your roof type, materials, and price range.

Underlayment for a Roof: What is it?

If you don’t know what roofing underlayment is, you can’t make an informed decision on synthetic vs. felt underlayment. Roofing underlayment is a waterproofing layer that roofers apply directly to the roof deck to give an additional layer of protection from the elements.

Rain, snow, and wind can cause damage to your home’s roof, which is why this product helps to protect it from these elements.

Types of Roofing Underlayment 

Roof felt paper and synthetic underlayment are the two most common forms of roofing underlayment. Both options offer clear advantages and disadvantages. In any case, it is essential to examine them before deciding.

Felt Underlayment:

It consists of fiberglass mat and saturated paper plus asphalt. Its cost-effectiveness is often cited as its key selling point. Because it is less expensive than most synthetic underlayment, felt is a popular choice among homeowners wanting to save money.


  • Low cost
  • Breathability 
  • Easy installation


Though their low price is a plus, felt roofing underlayment has many disadvantages. Therefore, the effectiveness of felt underlayment as a moisture barrier is considerably diminished when exposed to the environment for periods longer than a few hours.

Felt underlayment has the following drawback:

  • Predisposition to tears (especially during installation and when exposed to high winds)
  • Wrinkles and buckles easily when wet (especially if the installation takes too long)
  • Installing a synthetic underlayment is easier since it is lighter in weight than a felt one.
  • Slick surface makes difficult installation.
  • Doesn´t resist boot traffic 

Synthetic Underlayment:

Usually, manufacturers use long-lasting polymers to make synthetic roofing underlayment to ensure dependability and endurance. This type of roofing underlayment is becoming increasingly popular because of its increased moisture resistance and endurance against the weather. Compared to synthetic underlayment, roof felt paper provides the best protection from the weather.

Synthetic roofing underlayment is made from a variety of different materials that are not standardized. So, producers can follow different manufacturing processes, resulting in a wide range of performance levels. 

Synthetic roofing underlayment benefits and drawbacks to consider include the following:


Installing synthetic roofing underlayment is a cinch thanks to its strength and ease of use. In contrast to felt, synthetic roofing underlayment is significantly more durable and long-lasting. It is durable, water-resistant, safe to use, and easy to install when you know how.

Among the most important advantages to consider are these:

  • Easy installation
  • Water-repelling
  • Strong, long-lasting design with excellent tearing resistance
  • Resistance against UV radiation, water, and wind. It resists weather exposure better than felt underlayment.
  • Higher heat tolerance
  • It can withstand boot traffic. So, installation is a lot easier.
  • Lightweight


As you can see, synthetic roofing underlayment provides many advantages. However, there are also some drawbacks:

  • It is costly in comparison to felt
  • A lack of standardization exists among manufacturers

What Is the Right Underlayment for You?

Let us know what you think: synthetic or felt underlayment? In terms of cost, felt underlayment is the most cost-effective solution. But, if you are looking for the most long-lasting, dependable, and sturdy option, synthetic is your best bet.

For the best underlayment for your roofing materials, consult a roofing expert. 

Make sure you’ve done your homework and always seek the advice of a qualified professional. Are you planning to install a new roofing underlayment on your house? This guide will assist guarantee that you get the most out of your money.

For more information, contact RRG Roofing at 678-326-4951. We service areas in Dahlonega, Blairsville, Hiawassee, and Alpharetta, GA.

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