Signature Exteriors

Roof diagram

The Importance of Roof Underlayment

Shingles and rubber membrane surfaces receive the most attention on any new roofing project. Underlayment is a critical component of a roof structure that cannot be overlooked. Roof underlayment is an essential component for all roofing systems. Many property owners may not even know about it. We aim to change that in this blog post as we take a closer look at what you need to know about roofing underlayment and why it is vital to any roofing project. Here is a look:

What is Roofing Underlayment?

Simply put, the roofing underlayment is the protective barrier that is installed onto the roof deck under the shingles. Roof decking, or sheathing, is commonly made of plywood and is installed to create the initial roof surface over the rafters or trusses in a home’s attic area. While this helps create a barrier between your home and everything outside of it, the underlayment offers another barrier to keep moisture out and your roof (and home) protected. Finally, shingles are installed over this underlayment barrier. There are essentially three layers – the shingles, underlayment, and sheathing – protecting your home from the conditions outside of it.

Types of Roofing Underlayment

Different types of roof underlayment

There are three main types of roofing underlayment: synthetic, self-adhered, and felt. Here is a closer look at each of these types:

  • Synthetic: An increasingly popular underlayment material, this synthetic material tends to offer great strength to weight ratio. It is known for its water and mold-resistant properties.
  • Self-adhered: Self-adhering underlayment offers a sticky backing, so it installs easily to the roof deck and creates a strong seal between the two surfaces. However, self-adhered decking is typically best utilized in areas where water may collect or where intrusion could persist, such as eaves and valleys and around chimneys and skylights.
  • Felt: Also known as tar paper, felt is an older underlayment material that many contractors still use today. It is available in two standard weights, 15 LB & 30 LB, and, when installed correctly, will perform as an effective barrier.

What does Roofing Underlayment do?

We hinted at some of the importance of roof underlayment in the previous section. However, it is worth diving into more of the specifics. Here is a look at three reasons you should not overlook roof underlayment.

It Serves as an Extra Layer of Roof Protection

As noted above, roof underlayment is part of a triple threat to keeping your roof working well and your home safe. Think of this barrier, sandwiched over the roof deck and under the shingles, as an additional layer of protection. Roofs that are installed without underlayment are more susceptible to damage.

It Can Help Prevent Water Damage, Intrusion

Roof underlayment is designed to prevent water intrusion and help ensure the water runs down your roof to your gutters. Roof underlayment is especially helpful in acting as a temporary shield if you have missing or damaged shingles.

Underlayment can help safeguard your home against property damage, such as ice dams in winter. Ice dams form when snowmelt on your roof refreezes when it reaches the colder gutter. Ice dams can then prevent any subsequent runoff from draining correctly. Without quality underlayment, pooled-up water on the roof surface can seep into attics and ceilings.

It is Important During Roof Installation

Finally, any new roof that is installed without underlayment is leaving itself more susceptible to property damage. Make sure you take the time to speak with your contractor about the importance of underlayment and what type of material they suggest for your next roofing project.

Contact Signature Exteriors Today

For more information on the importance of roof underlayment, contact Signature Exteriors today. We pride ourselves on installing new roofs with the highest quality of workmanship and materials. Contact us today for more information and to receive an estimate on your next roofing project.