Your Ultimate Guide to Rubber Underlayment

Your Ultimate Guide to Rubber Underlayment

A lot of homeowners think rubber roof underlayment is just a modified type of rubber roof. The truth, though, is that EPDM roofs are actually a single-ply membrane that works as an external roof and an underlayment in one. 

Most roofing companies in Charlotte, NC, will tell you that if you want your roofing’s lifespan to be much longer, you should definitely consider installing an underlayment. This will not just lengthen the roof’s lifespan but that of your whole house, too. 

Your roofing is your home’s primary protection against the harsh weather elements – from the sun’s scorching heat to rainstorms and snow. With proper installation, your roof could last for years. In case the roofing material gets damaged severely, the underlayment will serve as the final line of defense. That’s how vital an underlayment is. 

Rubber roof underlayment

In this post, Southern Premier Roofing, a trusted roofing contractor in Charlotte, shares all the information you should know about rubber roof underlayment:

Table of Contents

What Exactly is Rubber Roof Underlayment

Underlayment is a protective layer of material that is installed underneath the external roof, and rubberized asphalt is one of the materials used for this purpose. The manufacturing process for the rubber roof underlayment is similar to that of EPDM roofing. 

Recycled rubber is often the material used by manufacturers. They get rubber from used and worn-out tires, discarded tubing, boots, and more. They mix in slate and sawdust during the manufacturing process to make the underlayment material more durable. Aside from that, manufacturers also add specific percentages of asphalt, polyester, and polyethylene, so the result is a highly durable, weatherproof product with high heat resistance. This is one of the reasons rubber underlayment is perfect for materials like metal and shingle roofing. That said, rubber roof underlayment is relatively more expensive than EPDM roofing. 

What Are the Pros and Cons of Rubberized Underlayment?


Some of the advantages of rubber underlayment include:

  • The installation cost is lower because it’s easy to apply
  • It can last for about 50 years or so, as there are few seams which mean there’s a lower chance of water seeping in
  • It’s the only waterproof option available for this purpose
  • It is UV-resistant
  • It is more durable than pure asphalt because it doesn’t contract, expand, or crack
  • It is easy to repair – in the rare occurrence that a tear appears, it can easily be fixed using a special type of tape.


There aren’t that many drawbacks with rubber underlayment, but here is a couple to remember:

  • Rubber underlayment can come in different forms, so you need to know for sure that what you’re getting is fire-resistant because some of them are not. 
  • You will have to hire a professional to install this kind of underlayment, which means additional cost.

Why Your Home Needs Rubber Roof Underlayment

There are several reasons for you to get this type of underlayment:

It Can Effectively Protect the Internal Roof from Moisture

Rubberized underlayment can efficiently catch water or moisture that may be missed by your metal or shingle roofing. If you have sloped roofing, the underlayment also ensures that the water goes straight to the gutter system. 

This may seem simple, but it is a crucial job as it can prevent the formation of mold and mildew in your roofing system. On top of that, it also helps keep the internal roof safe from damages during heavy storms. 

For homes with low slopes or flat roofing, a rubber underlayment can ensure that there will be no ponding damages. That means that property owners won’t have to worry about premature roof replacements that could cost them thousands. 

It Enhances Fire Resistance

Because of the high-heat-resistant features, most rubberized underlayments won’t catch fire. Most rubber roof underlayments are of the same grade as fireproof rubber. This is the same type of fireproof rubber that is used on sofa and insulation, among others. Passenger train cars also make use of this material because it is not only insulating but also fire-retardant. 

It Helps Prolong the Lifespan of Your Home

The roof is among the main protective barriers of a property. Because a rubberized underlayment can extend the life of the roofing system, it also maintains the strength of the external walls of the home. 

Rubber underlayment can last for decades, so it can provide support to your roofing system until the time that your roofing requires replacement. It may still even be good enough to support new roofing.

How to Know When to Replace Rubberized Underlayment

After a few decades, underlayment can begin to stop functioning correctly. Because you can’t dismantle the roofing system to check if your underlayment is still in good condition, you just have to know what signs to look out for that tell you there could be a problem with your underlayment:

Discoloration on the Ceiling

If there is some discoloration on your ceiling, that’s a telltale sign that there are leaks, meaning your underlayment has been compromised. It’s possible that there’s ponding, especially if you have low-slope roofing. 

Growth of Mold

Do your family members suffer from nasal issues, or have you been feeling sick lately? It could be because of mold growth in your home. If mold is growing in high concentration in your home, it may be because there’s moisture in the underlayment. 

Roofing felt is an ideal breeding ground for mold and mildew. Because it’s highly permeable, moisture can easily seep into the roofing joists. If there’s any sign of mold, it’s best to contact a professional who can test the property for mold. Do this immediately because it can be dangerous to your family’s health. 


Rubber roof underlayment is indeed one of the best roof underlayment types that you can have for your home. It offers durability, longevity, strength, insulation, fire resistance, and more. Of course, for you to get all the benefits that a rubberized underlayment provides, you need to make sure that you’re getting it installed by seasoned and reputable roofing contractors. 

Southern Premier Roofing is among the top roofing companies in Charlotte, NC, that you can trust with anything roofing-related – from regular maintenance to simple repairs and whole system installation such as roof replacements, sidings, gutters, and paintings to Raleigh, Charlotte, and Fayetteville, NC, as well as Boise ID. Contact us today to get a quote for your roofing project!

"*" indicates required fields

This field is for validation purposes and should be left unchanged.

Request Estimate