Choosing the Right Underlayment for Your Metal Roofing Installation

Skywalker Roofing Company
Choosing the Right Underlayment for Your Metal Roofing Installation
December 9
By Luke Wilson | Metal Roofing, Roofing

Metal Roof Installation

Metal roofing has become a very popular roofing option in the US for many reasons. But if you’re seriously considering having a metal roof installed, you should also know more about proper roof underlayment requirements. Choosing the right underlayment for a residential or commercial project is every bit as important as choosing the right roofing material. Underlayment is the layer beneath your roofing system that serves as an extra weather resistance barrier, ultimately providing greater moisture protection. But this layer of protection isn’t optional; it’s really essential to a proper metal roofing system. Ready to learn more about how to choose the right underlayment option for your metal roofing system? Then keep on scrolling!

A Metal Roof Is Really a Better Choice

While shingles are still a very popular choice for American residential roofs, that doesn’t mean that asphalt shingles are necessarily the best available roofing material option. Looking for a truly durable roof that’s made to last, and won’t need replacing during your lifetime? Think metal! It’s amazingly durable, requires significantly less maintenance than shingles, and can last many times longer with a proper metal coating applied during metal roofing material manufacturing. In addition, a modern metal roof looks great, provides that signature, soothing pitter-patter sound during a rainstorm, and is also better rated for handling both wind and snow loads.

Some Specific Benefits of Metal Roofing

Modern metal roofing is engineered to be durable and long-lasting, but there are many other aspects of metal roofing that are worth noting, as well. Here are a few facts of note:

  • Can easily last 75 years or longer with proper coatings and proper roofing installation.
  • Designed to withstand strong wind gusts, flying debris, hail, and snow accumulation better than most roofing materials.
  • Metal is a class A fire-rated roof covering, and metal is also much better at deflecting & diffusing the impact of lightning strikes.
  • Metal roofs don’t crack, warp or peel over time, unlike comparable roofing fabricated with asphalt or wood.
  • Metal roofing helps to decrease ambient roof temperature in comparison to what you’d experience with an asphalt roof. This will help to extend the service life of your roof, attic, and supporting infrastructure.
  • Metal roofs help to make your structure more energy-efficient, thanks to their ability to reflect more solar radiation while absorbing less heat. One positive result is that less interior cooling is needed during the warmer months, meaning you’ll save on your energy costs.

What is Roof Underlayment?

Underlayment is a type of vapor barrier or water-resistant material that’s placed beneath the top roofing layer. It’s designed to add an extra layer of protection against weather impacts and moisture infiltration. Roof underlayment is typically placed beneath all external roofing materials, and is attached directly to the roof decking or sheathing. Three common types of underlayment for metal roofs include felt, self-adhering membrane, and synthetic sheet.

roof underlayment

Without any underlayment in place, the roof (and consequently, the rest of the home) are more prone to exposure to weather elements like wind and moisture. A proper underlayment can also help prevent the infiltration of chemicals or resin that can leach out of your roofing materials over time. Finding and using the right underlayment for your metal roof is an important way to not only protect your roof, but also to help promote its longevity.

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But, Does a Metal Roof Really Need an Underlayment?

That’s a fair question to ask. You probably know that underlayment is essential for a shingle roof, but is it really needed for a metal roof? There’s a popular misconception that underlayment or similar insulation isn’t a requirement for metal roofing. While it’s true that a vapor barrier or something similar may not necessarily be essential in terms of maintaining the structural integrity of your metal, it does still offer important benefits for your roof system and home. Having the right underlayment in place will help prevent moisture from infiltrating, and will also help prevent condensation from collecting inside your attic space. The fact of the matter is that entrapped moisture can accelerate the deterioration of any roof, even one which is comprised of sturdy metal roofing. It’s also a good idea to choose an underlayment that’s designed to match the anticipated lifespan of your metal roofing materials, in order to help ensure the longevity of the entire roof system.

Common Underlayment Options

What’s the best underlayment choice for your metal roof? A standing seam metal roof is a significant investment, so it’s important to create the best support system which will contribute to the best protection for your roof and home. Here are some things to keep in mind when considering three common metal roofing underlayment options:

Felt Underlayment (Asphalt Felt or Tar Paper)

Felt Underlayment

It’s known by many names, including felt paper, tar paper, and asphalt-soaked felt. But no matter what you call it, felt underlayment is the most common underlayment material used for steeper-sloped metal roofs. One of the biggest reasons for its popularity is the simple fact that felt underlayment is the cheapest material option. But just keep in mind that – as is true for many things – cheaper isn’t always better. Asphalt felt is reliably water-resistant, but it doesn’t tend to endure high-temperature environments very well. It also doesn’t last as long as other underlayment materials, and is likely to fail long before your metal roofing is set to expire. In addition, felt underlayment isn’t the best design option for low-slope metal roofing protection.

Self-Adhering Membrane

Self-Adhering Membrane

Self-adhering membrane underlayment is a peel-and-stick product designed to be applied directly to roof decking. It usually includes either a rubberized asphalt or butyl-based adhesive that’s mounted on a polyethylene carrier sheet. Self-adhering membrane performs better than felt underlayment in high-temperature environments, presents more of an air barrier, and is more helpful for ice dam protection in sensitive locations like eaves, valleys, and dormers. But one downside of self-adhering membrane is that it’s not known to perform very well in low-temperature environments. Another challenge with self-adhering membrane is in getting it installed properly. If not handled correctly, a botched installation can result in your membrane becoming peeled back over time, which will then leave your roof more vulnerable to infiltration.

Synthetic Sheet

Synthetic roofing underlayment

Synthetic underlayment for metal roofing is a newer technology that’s become more prevalent in recent years. It’s manufactured by weaving or spinning together either polyethylene or polypropylene with a polymer, in order to form a protective barrier between the roofing material and decking. Synthetic sheeting offers lots of advantages over some of the other options. It’s very durable, because it uses thermoplastic polymers which are more resistant to tearing, moving, and other damage. It’s also very tolerant of high temperatures, and delivers the longest underlayment lifespan. Synthetic is also incredibly effective at keeping out moisture, so it’s also very important to build in a proper ventilation system for your metal roof. Synthetic sheeting is typically more expensive than some comparable underlayment options, but it also provides the most reliable performance and better product longevity.

Corrugated Metal Panels vs. Standing Seam Metal Roofing

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Partner with the Right Roofing Provider – Skywalker Roofing!

At Skywalker Roofing, we pride ourselves on installing roof systems of superior quality with superior workmanship. There’s a reason we’re willing to claim that a Skywalker roof is the last roof you’ll ever need! We have all the materials, tools, training, and expertise needed to craft and install your custom standing seam metal roof right on your property. In addition, we believe in creating the best possible support system for your roof, which is why we offer a Total Protection Roofing System from Owens Corning that features Titanium Synthetic Underlayment. In fact, Titanium Synthetic is honestly an ideal choice for roofs of all stripes, including both metal roofing and asphalt shingles.

While selecting the right roofing materials is certainly an important decision, choosing a local roofing contractor you can trust is even more important. . To that end, Skywalker Roofing provides premium quality metal roofing installations throughout our service area. Looking for a grade-A roofing provider for any and all types of roofing projects? If you’re located within our NC or VA service areas, then you need look no further than Skywalker! We’re proud to serve the NC Piedmont Triad, Piedmont Triangle, Lake Norman area, and southern VA region (including Roanoke and points south). In addition, our happy customers give us an average rating of 4.9 out of 5 stars on review platforms like Google, Facebook, BBB, Guild Quality, and more!

Ready to get the last roof you’ll ever need? Reach out to us today by calling +1 (336) 627-5596. One of our friendly experts will be glad to listen to your needs, and we’ll take the time to answer all of your questions. We’ll also be glad to schedule a FREE home or business inspection and personal consultation for you. We’d love to have the opportunity to show you the Skywalker Roofing difference!

Luke Wilson

Luke Wilson

Owner - Skywalker Roofing

Luke Wilson started working on roofs with his dad when he was a teenager, and eventually launched Skywalker Roofing in 2003. Skywalker operates in 5 locations across NC & VA, and now includes windows, siding, and other exterior services. Luke also hosts the popular Roofing Mythbusters series on YouTube.

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