The 5 Most Important Tips for Installing Synthetic Roofing Underlayment

There are so many advantages to synthetic roofing underlayment—and many of those advantages are things that will make installation easier. For example, Epilay’s ProtecTite line of synthetic roofing underlayment rolls out easily and smoothly, with no lumps or bumps. With that, even the heaviest rolls (ProtecTite Platinum), weigh half as much as felt underlayment, which makes it much easier to handle synthetics on a rooftop.

You know there are a lot of benefits to synthetic underlayment—but what about tips for installation? We’ll show you some of the most important things to know so that your next synthetic underlayment job goes smoothly.

1. Follow Manufacturer Instructions

We mentioned it in a related article featuring tips for installing peel-and-stick underlayment, and we’ll say it here, too: It’s always best to follow manufacturer instructions when installing any kind of underlayment, including synthetic. There are two reasons for that.

First is the warranty. Neglecting to install the underlayment according to instructions can void the warranty.

Second, the installation instructions often contain information that can help you follow local building codes. While the instructions won’t lay out building codes for specific areas, they will show you how to use the underlayment for different applications like valleys in places where such uses are permitted.

2. Plan for Your Roofing Material

With supply chain disruptions being common, especially during storm season, there is always the chance that homeowners could decide to switch primary roofing materials (for example, from asphalt shingles to metal) if the wait for the original material proves longer than they’d like.

The problem is, certain underlayments are better for certain types of roofing. For example, if you install our strongest non-adhesive underlayment, which is ProtecTite Platinum, the underlayment will have the durability to support any type of roofing, including heavy materials like clay tiles or slate. But if you install our lightest underlayment, which is ProtectTite Plasfelt, you’ll need to stick with lighter roofing materials like shingles or metal.

 

3. Don’t Skimp Surface Preparation

It’s not as much of an issue on new construction as it is on re-roofing jobs, but either way, you’ll need to be thorough about surface preparation to prevent damage to the underlayment. Make sure that fasteners aren’t poking up to avoid tears, and just prior to installing the underlayment, be sure to sweep off the roof or use a blower to remove any debris.

4. Use the Right Fasteners

The right fasteners ensure that you’re compliant with building codes and the warranty, and they prevent damage or premature weakening of the roofing system. For Epilay’s synthetic roofing underlayment, approved fasteners include:

Corrosive-resistant roofing nails with 3/8-inch heads

Plastic cap nails or staples

Hammer tackers with 3/8-inch crowns

7/16-inch crown staples

If the underlayment will be exposed for an extended period, use plastic cap nails or staples, or 3/8-inch head roofing nails to make sure the underlayment stays in place and maintains as much moisture resistance as possible.

5. Pay Attention to the Printed Pattern

When you unroll Epilay’s synthetic roofing underlayment, you’ll notice a few things. For starters, all of our underlayments feature GripWalk, which is a high-traction surface made to make roofing safer. The surface is also light-colored, which helps keep it cooler on rooftops baking in the hot sun.

Beyond that, you’ll also see printed marks across the surface of the underlayment. The horizontal lines are lap marks, which means that when you’re rolling out underlayment horizontally, line the upper layer up with the lap mark on the lower layer to easily get your overlaps right.

You’ll also find nail marks. Follow these as a guide to installing fasteners so that the underlayment has both maximum wind resistance and resistance to foot traffic.

The great thing about ProtecTite underlayment is that it’s easy to install. If you’ve worked with asphalt felt before, then you’ll be surprised how much easier it is to work with synthetics. All you’ll need to do is follow the tips above to make sure the new underlayment is installed correctly.