When homeowners in Northwest Arkansas invest in a new roof, their attention is almost entirely focused on the shingles. They spend hours agonizing over the color, debating the merits of architectural versus 3-tab styles, and envisioning how the final product will boost their home’s curb appeal. While the shingles are the visible face of the roof and the primary shield against the elements, they are not completely waterproof on their own. The true unsung hero of any reliable roofing system lies hidden beneath the surface. At Richardson Roofing, we know that a roof replacement is only as strong as its foundation, which is why we emphasize the critical importance of high-quality roofing underlayment.
Roofing underlayment is the protective layer installed directly over the wooden roof decking, serving as the final barrier between the outside weather and the interior of your home. It is installed before the shingles are nailed down, acting as a secondary line of defense. Understanding the vital role underlayment plays can help you make informed decisions during your next roofing project and ensure your home remains dry and secure for decades.
The Secondary Water Barrier
The primary function of roofing underlayment is to act as a secondary water barrier. Asphalt shingles are designed to shed water, overlapping each other to guide rain down to the gutters. However, shingles are not a seamless, impenetrable membrane. During severe Arkansas thunderstorms, high winds can easily drive rain upward, forcing water underneath the edges of the shingles. Without underlayment, this wind-driven rain would immediately soak into the wooden roof decking, leading to rot, structural damage, and interior leaks.
A high-quality underlayment catches this infiltrating water and safely directs it down the slope of the roof, protecting the vulnerable wood beneath. This secondary barrier is also crucial during the winter months. When ice dams form at the eaves of the roof, melting snow is forced backward, creeping up under the shingles. A specialized waterproof underlayment, often called an ice and water shield, is installed at the edges and in the valleys of the roof specifically to prevent this trapped water from destroying the decking.
Protection During Installation
Underlayment also serves a critical role before the roof is even finished. The process of tearing off an old roof and installing a new one rarely happens in a single day. Once the old shingles are removed, the bare wooden decking is completely exposed. If an unexpected rainstorm rolls in before the new shingles can be installed, the decking could be ruined.
As soon as the old roof is removed, our roofing crews immediately roll out and secure the underlayment. This provides immediate, temporary waterproofing for the home, ensuring that the interior remains dry even if the weather turns sour mid-project. A high-quality synthetic underlayment can be left exposed to the elements for weeks without degrading, providing immense peace of mind during the installation process.
Preventing Chemical Degradation
Another lesser-known function of underlayment is acting as a chemical barrier between the wooden roof deck and the asphalt shingles. Wood naturally releases resins and sap over time, especially as it heats up in a hot attic. If asphalt shingles are installed directly onto bare wood, these natural resins can react chemically with the asphalt, causing the shingles to prematurely dry out, crack, and fail.
The underlayment provides a necessary separation layer, preventing this chemical interaction and ensuring the shingles reach their maximum intended lifespan. Additionally, underlayment provides a smooth, uniform surface for the shingles to lie on, preventing the rough texture of the wood decking from telegraphing through and ruining the aesthetic appearance of the finished roof.
Types of Roofing Underlayment
Not all underlayments are created equal. Historically, the industry standard was asphalt-saturated felt paper (often called tar paper). While affordable, felt paper is prone to tearing, absorbs water over time, and degrades quickly if left exposed to the sun.
Today, the gold standard is synthetic underlayment. Made from woven polymers, synthetic underlayment is incredibly strong, highly resistant to tearing, and completely waterproof. It is lighter, safer for roofers to walk on, and provides vastly superior protection compared to traditional felt. At Richardson Roofing, we utilize premium synthetic underlayments to ensure our customers receive the highest level of protection possible.
A roof is a complex system, and every component must work together to protect your home. Do not let a contractor cut corners by using cheap, outdated underlayment beneath your expensive new shingles. Find Richardson Roofing on Google to see why local homeowners trust us, and contact our team today to ensure your next roof replacement is built on a foundation of quality.