As any roofing contractor knows, there are lots of factors to consider when choosing an underlayment. Some underlayment works better for one type of roofing over another, while other underlayment products are better designed to withstand moisture, UV rays, and other environmental concerns.
If you’re wondering what to use, here’s an overview to show you which products will work best in a variety of situations.
Storm Damage or Delays Expected? Choose Synthetic
Ideally, when a roof needs replacement or repair, you’re able to do the entire job immediately, including putting the primary surface in place, whether it’s shingles, metal, or another material.
The problem is, in a lot of instances, the situation is less than ideal—and that’s particularly true these days while supply chain disruptions and delays are common. While most roofers are aware that it’s best not to start a roofing job until all of the materials have arrived, the weather doesn’t always give you a choice. Storm damage can remove primary roofing surfaces and damage the underlayment beneath, which means that clients are relying on you to come through with a replacement quickly before leaks do structural damage to their home.
So what then? You could be caught in a tough spot, with nothing to place on the roof while you wait for shipments of new shingles or sheet metal to come in.
Or you could go with synthetic underlayment as a stop-gap to protect the roof in the meantime.
If you’re wondering which Epilay product to choose for your roofing products, here’s an overview to show you which products will work best in a variety of situations. Products from our Protectite line are water repellant and can be exposed to UV rays for up to one year. Our peel-and-stick products, Plystik Plus and Plystik SA-250 will give you water resistance and UV resistance for up to 180 days.
Speaking of the Weather…
Protecting storm-damaged roofs while you wait on supply shipments isn’t the only weather-related reason why you might choose heavy-duty synthetics or peel-and-stick underlayments. You should also account for the kinds of weather common in your region, and use the types of underlayment that will offer the best protection should the new roof become damaged.
In windy areas, for example, choose heavier underlayment that isn’t as prone to lifting, or go with peel-and-stick, which is highly resistant to wind. Cold, snowy climates benefit from peel-and-stick around the roof’s edges where ice dams form, and in rainy areas, peel-and-stick is smart in valleys that will end up channeling lots of water.
What happens when you need to install a new roof in cold weather? Asphalt felt can be tough to work with because when temperatures dip, the tar stiffens up—and that leads to the paper cracking as you try to unroll it. Synthetics get around this easily, featuring great rollability even when it’s cold outside.
Choosing Based on Roofing Material
Barring emergencies and storm damage, the next best way to choose is based on the primary roofing material that you’ll be installing. In general, heavier roofing materials should be backed by a heavier-duty underlayment. This not only prevents damage to the underlayment itself but also the roof deck. Read on for a list of common roofing materials and the underlayments that work best with them.
- Asphalt Shingles: Asphalt shingles are a lightweight roofing option, and they’re also one of the most common options. Just about any underlayment will work well beneath them, from synthetics to asphalt roofing felt. Making the right choice here means considering other factors, like building codes, costs, and longevity. Our Protectite Plasfelt is an option that may interest you. It’s our thinnest, lightest, and most cost-effective product to date, but plenty tough enough to work well beneath shingles or even metal roofs.
- Residential Metal Roofing: This is another lightweight roofing material—but it does weigh a bit more than shingles. Here again, you can use almost any underlayment so long as the code in your area allows for it. That being said, because metal is heavier, it’s often wise to step up your underlayment game and use a heavier product like Protectite Superior.
- Slate Roofing: While it’s less common than shingles or metal, you’ll still see the occasional slate roof—and slate is incredibly heavier. Thinner, lighter underlayments just won’t stand up to it long term. You’ll need a heavier product, like Protectite Ultra, Platinum, or even Plystik Plus.
- Concrete and Clay Tiles: For these roofs, we recommend either Protectite Platinum or Plystik Plus. These materials are even heavier than slate roofing, in most cases. A heavy-duty underlayment is a necessity.
Choosing Based on Building Codes
In many areas, building codes permit everything from #15 felt to the toughest of synthetics—but in other areas, building codes are much more stringent. Take Florida, for example, which has some of the toughest requirements for roofing anywhere in the United States, namely because roofs there need to be able to stand up to hurricane-force winds.
Here, you’ll need at least #30 underlayment or the equivalent—which would be an underlayment that meets ASTM D 226 Type II or ASTM D4869 Types III and IV. All Epilay synthetic roofing underlayment meets these standards, making them a safe choice for areas like Florida with tougher building codes.
The underlayment options provided by Epilay are designed to perform well under a variety of conditions, and best of all, each underlayment is versatile enough to work with several different kinds of roofing material. Use this guide to choose the right underlayment for your projects based on roofing materials, building codes, weather concerns, and more.