A roof sits atop a home to provide a shield from heat and rain. The protection that homeowners get from a strong and effective roofing system remains essential year in and year out. Most people would easily understand that a roof forms the exterior portion of a house but are not familiar with the roofing system and how it serves its purpose properly.

What makes a roof durable after so many years of being exposed to different types of weather? Keep on reading to know the importance of roofing underlayment and everything that comes with it.


What is a Roof Underlayment?

The roofing underlayment serves as the protective layer on a roof deck’s surface. Most of the time, it is water-resistant that prevents water intrusion. A roof underlayment is often necessary as it functions as a barrier protecting a home from exposure to rain, snow, and heat. It holds so much importance because without it, a house is vulnerable. 

Understanding how roof underlayment works is essential for homeowners who plan to choose the best type of roof underlayment for their homes and make their roofs last for a long time. It is also important to know the different types of roof underlayment options to know what best fits their needs.


Different Types of Roof Underlayment

Roof underlayment has various types, like synthetic and felt roof underlayments. They vary based on performance to withstand severe weather conditions. To equip a roof with complete protection, each type of roof underlayment has its specific capacity. Below are the three major types of roofing underlayment that homeowners can choose from. 

Read also: Choosing the Ideal Tile Roof Underlayment.

The asphalt-saturated felt is a type of roof underlayment that is water-resistant. It was initially the most popular roof underlayment option before synthetic products appeared. Asphalt-saturated felt is also known as felt paper or tar paper as this material is a combination of polyester, bitumen, and asphalt. Its base layer showcases a flexible substance just like tar. Its water resistant-component is asphalt-saturated basemat. Felt enhances the stiffness of a roof deck and makes it durable from debris, hailstones, and impact from hard objects.

The rubberized asphalt offers a waterproof material that is made up of high concentrations of rubber polymers and asphalt. From all of the roof underlayment options, this has a 100% waterproof seal. Having waterproof materials can work effectively for snowy or colder regions. Rubberized asphalt is potent against potential water damages.

Usually, this comes with a self-adhesive that is protected by a peel-off membrane. Rubberized asphalt also functions as a self-sealing underlayment. Sealing around fasteners would be better with rubberized asphalt. Fiberglass or polyester film are included in some rubberized asphalt roof underlayments for preventing moisture build-ups.

In terms of pricing, this roofing underlayment is more expensive. Materials utilized to form it contribute to its pricing. 

Most professionals would prefer utilizing non-bitumen synthetic underlayment nowadays. This type of roof underlayment is more likely to be used on modern roofs. It is incorporated with fiberglass and saturated with asphalt. This presents an effective elasticity and tear resistance.

Due to the water-resistant characteristic of a non-bitumen synthetic underlayment, it does not absorb moisture and also protects against wrinkles and fungal growth. This type of underlayment has been preferred not just because of its non-skid and lightweight qualities but also due to its resistance to UV rays. It helps with preventing excessive heat damage to the surface of a roof. 


Advantages of a Roof Underlayment

Various types of weather conditions and elements test a roof over a course of time. A roof underlayment functions essentially and below are the key advantages that homeowners should know. 

Shingles make the exterior cover of a roof deck, reflecting sunlight, rain, and wind from the surface of the roof. An overlap from each other leaves very small spaces around the corners. These spaces let both moisture and water pass through on heavy rains. On hot days, the attic space also builds up heat and weakens shingles. With the help of roofing underlayment, protection is provided against different weather conditions that shingles cannot endure alone.

Moisture build-up causes the shingles to weaken over time. Exposure to different types of weather makes the exterior surface brittle over time. Having a water-resistant roofing underlayment makes water droplets slide off the roof’s surface. Synthetic underlayment and asphalt-saturated felt roof underlayment are the most recommended types. 

If a home’s roof is made up of hips, dormers, and valleys, these areas are more likely to leak on heavy onslaughts of rain. Usually, asphalt shingles are utilized to fight against water leakages. Using a waterproof roofing underlayment as a protective barrier should follow suit. The best type for preventing leakages is rubberized asphalt roof underlayment placed under a drip edge.


Comparing Synthetic Roofing Underlayment vs Felt

For steep-sloped roofs, asphalt-saturated felt roof underlayment is still the most popular option. This type is the longest-existing underlayment material. Installation of this roof underlayment type is also more common to most roofing contractors.

The non-bitumen synthetic underlayment is the more utilized type of most modern homes today. It also offers a more potent material composition that’s why more professionals prefer this today. When it comes to pricing, this one is more expensive compared to felt roof underlayment. 

Synthetic underlayment offers more roofing reinforcement and thus more benefits. For homeowners who are working on a very tight budget, traditional felt underlayment is not a bad option.


The Value of Roof Underlayment to a Home

Prolonging the life of a roof would be greatly affected by the essential role of roofing underlayment. A roof is exposed to different types of weather throughout the year. Its durability is tested by the elements. Thus, the need for proper roof underlayment is vital. Imagine the cost of repairs due to extensive damage compared to considering roof underlayment from the start.

Asphalt-saturated has been a trusted type of roof underlayment through the years but the more modern option chosen by today’s professionals is synthetic underlayment. For homeowners with a tight budget, rubberized asphalt may serve as a viable option as its works as a durable barrier that could best fight against water leakage.

Read also: Top-tier Synthetic Underlayment Manufacturers

Editorial Contributors
avatar for Matt Greenfield

Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

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