Roofs are structural systems made with multiple parts and layers. Depending on the type, your roof may have rafters, joists, flashing, soffits, gutters, downspouts, and other components. Shingles and tiles are the most visible layers. They are installed on top of the underlayment, which is vital to protection and longevity.
Understanding Roof Underlayment
Roofing systems are designed to endure inclement weather, temperature shifts, and pest infestations. While the shape and installation of the shingles promote drainage, the layer beneath guards against water penetration.
The underlayment sits directly on top of the roof deck. It’s a flat layer that provides essential protection beyond what the outer roofing material alone offers. Its primary function is to provide an initial layer of protection against precipitation, wind, and extreme temperatures. Although the underlayment is not the topmost layer, it’s functional in terms of acting as a barrier.
The water-resistant properties of the underlayment make it crucial to the roofing system. In new construction projects, the underlayment protects the structural deck, rafters, beams, joists, and insulation. According to the International Building Code, all roofing systems must feature an underlayment. The only exception would be specialty roofs with metal sheeting as the topmost layer.
The underlayment must provide a smooth and consistent surface for the application of the final roofing materials. They are applied over the deck and sheathing to create a waterproof protective layer. If your home loses a few shingles or tiles during a storm, the underlayment will prevent leaks. If hail accumulates and melts on the rooftop, the slope of the underlayment will guide water to the drainage system.
Beyond its waterproofing aspect, the underlayment contributes to the overall longevity of the roof structure. When properly installed, the underlayment prevents moisture from reaching the vulnerable wood decking and framing. This reduces the risk of rotting, mold growth, and structural damage. Proper underlayment installation involves adequate overlapping and secure fastening. This is paramount for the longevity and integrity of any roofing system.
Our roofers always ensure that the roof deck and sheathing surfaces are ideal for underlayment installation. We insist on thorough surface preparation, particularly around sections that should be covered with self-adhering underlayment. Roofing projects that involve reconditioning need more detailed deck inspections to ensure there aren’t damaged or rotting sections.
After preparing the surface, we carefully unroll the underlayment material to check for proper alignment and overlapping of seams. The specifications for aligning the pieces depend on the brand. Each section is firmly fastened or adhered to bond with the surface, paying close attention to seams and edges. Doing this is crucial to prevent water infiltration and hidden leaks. Our roofers follow specific nail patterns and spacing to prevent tearing or lifting during drastic temperature changes. We pay special attention to sealing around roof features like vents, pipes, and chimneys.
Underlayment Types and Materials
The type of underlayment and primary materials for a roofing project are determined by applications and regional climate conditions. In the Georgia and South Carolina regions, the underlayment must withstand heat, humidity, and heavy rainfall. You want materials that can resist degradation from ultraviolet rays while providing temporary water absorption without filtration.
The most used underlayment materials include felt, self-adhering, and synthetic types. In the self-adhering category, you can find rubberized asphalt materials that are also available in non-adhesive versions. Some metal roofing projects call for specialty underlayment if they include attics.
Felt
This is what many people know as “roofing paper.” It’s called felt because its texture somewhat resembles the textile fabric. However, the formulation includes pulp, fiberglass, and asphalt. As a popular low-cost underlayment solution, roofing paper is easy to source. Unfortunately, it only has a lifespan of about 10 to 20 years.
Although roofing paper tends to be heavier than other types, it’s reasonably easy to install. Our roofers have ample experience working with this material, which is sufficiently flexible to ensure full coverage. When properly installed, felt underlayment provides a good barrier against precipitation. You can count on the protection that roofing paper provides during storms. It can also withstand minor shingle or tile damage.
As a popular underlayment solution, roofing paper is easy to repair and replace. If a heavy hailstorm causes damage to the shingles, tile, and underlayment, we can replace the affected underlayment section quickly. There’s a caveat when selecting roofing paper for a new construction project in our service area. Felt is more susceptible to tearing and damage because its organic components degrade over time. Climate change makes sunny and stormy seasons more intense, so roofing paper is not always the best choice.
Self-Adhering
As its name indicates, this underlayment type features a peel-and-stick method of installation that is gentler on the roof structure. Its formulation includes asphalt and rubber polymers supported by heavy-duty adhesive backing. This solution is less intrusive than roofing paper because there is no need for nails, staples, or screws.
Many roofing projects combine roofing paper with self-adhering underlayment sections. The adhesive properties create dependable waterproof sealing directly on the roof deck. For this reason, sticky underlayment is often used around vents, chimneys, skylights, and other roof features. A granulated surface enhances the weather resistance to provide a non-slip surface for safer installation.
By creating impermeable barriers, self-adhering underlayment prevents water from backing up under shingles. This added layer of defense results in peace of mind during severe weather conditions. The straightforward installation minimizes the potential for installation errors. This underlayment material lasts for up to 50 years or more, making it the underlayment option with the best longevity.
Synthetic
In recent years, synthetic underlayment has emerged as the most sensible solution for our region. When properly installed, synthetic underlayment is superior to roofing paper in terms of protection and durability. If you want a roof that will last five decades before replacement, we strongly recommend a weatherproofing synthetic solution.
The advanced polymers of synthetic underlayment make it more resistant, resilient, and protective. With this solution, you get formidable material strength and longevity. The rolls are lighter, larger, and easier to install. Some synthetic underlayment options improve breathability, thus allowing moisture vapor from the attic to escape.
Our roofers enjoy working with synthetic types because of their non-skid surfaces. Some roofing papers get slick and slippery with the morning dew and the dust generated by construction activity. Their synthetic materials provide better traction and secure footing that makes installation more efficient.
The initial cost of synthetic underlayment is invariably higher than roofing paper; nonetheless, the long-term benefits outweigh the upfront investment. The increased durability and resistance help to maintain the long-term integrity of the roof system. The lifespan of synthetic underlayment is approximately 25 to 40 years. This translates into fewer repairs and a longer overall lifespan, saving money in the long run. Compared to a felt underlayment, a synthetic one is generally less likely to wrinkle or crack compared to felt. Cracking and wrinkling often happen in regions with temperature swings. Felt can stiffen and crack in cold weather; synthetic rolls, on the other hand, are more flexible.
With almost two decades of roofing experience, Fraser Roofing, LLC has forged a solid track record of quality work and customer satisfaction. We specialize in all roofing services from inspections to emergency repairs and from storm damage remediation to full replacement. To get more information about the quality roofing services we provide in Metro Atlanta and the Upstate South Carolina region, contact Fraser Roofing, LLC today.
