Many folks in the US opt for metal roofing because of its multiple benefits. However, before you go on and finalize the metal roof, you should be aware of the essentials. Choosing the right roofing material is important, but choosing the right underlayment material goes a long way. This is why we will talk about the different types of underlayment materials for your metal roofing. Keep reading to expand your knowledge on this crucial aspect of your roofing.
What is a Roof Underlayment?
Underlayment helps add an additional layer of protection and weather resistance barrier. You can think of it as a water-resistant material that is placed under the top layer of your property’s roofing. Hence, the right underlayment can protect against moisture inflation and weather impacts. Roofing underlayment is attached directly to the roof sheathing and decking beneath the external materials. In short, metal roofing needs underlayment. Felt, self-adhering membrane, and synthetic sheet are the three popular types of metal roofing underlayments available.
Your Underlayment Options for a Metal Roofing
Metal roofing, especially standing seam metal roofs, is a great investment. Therefore, it only makes sense to have the top support system for your roofing. Below, we’ll mention some important factors regarding each underlayment option:
1. Felt Underlayment
You might know it as tar paper, felt paper or asphalt-soaked felt. It’s the most frequently used underlayment material for steep-sloped metal roofing. Usually, people prefer felt underlayment because it is a cheap option.
You can expect water resistance with asphalt felt, but it isn’t the best in withstanding high-temperature environments. Moreover, it lasts a shorter period than other underlayment materials comparatively. Thus, it might expire before the metal roofing. Felt paper is not a great design choice for low-slope metal roofing protection.
2. Self Adhering Membrane
As the name suggests, self-adhesive membrane underlayment is designed as a peel-and-stick product. This means you can apply it to the roof decking directly. This underlayment has a polyethylene carrier sheet with a rubberized asphalt or butyl-based adhesive mounted on top of it.
Compared to felt paper, this underlayment endures high-temperature environments better. Moreover, it is useful if you live in sensitive locations like valleys, eaves, or dormers since the self-adhering membrane provides ice dam protection. Plus, it can present an air barrier.
However, it might not be the best material in areas with lower temperatures. Furthermore, it can be tricky to install self-adhering membranes in a proper manner. And if you don’t handle it correctly, a botched installation might lead to the underlayment peeling off over time. As a result, your roof will become vulnerable to infiltration.
3. Synthetic Sheet
Nowadays, synthetic sheets are prevalent. This underlayment is a newer technology for metal roofing. Weaving or spinning together polyethylene or polypropylene with a polymer is how synthetic sheets are manufactured. They offer a protective barrier between the roofing material and the decking. Other than this, these underlayments are packed with benefits.
The thermoplastic polymers in a synthetic sheet make it resistant to damage like tearing and moving; therefore, it is durable. In addition, it can tolerate high temperatures and has the longest lifespan among underlayment materials. This is not all — synthetic sheeting effectively keeps out moisture. Even though it’s a tad bit expensive compared to other underlayment alternatives, it’s worth every penny.
What Should I Do?
Now that you know the fundamental facts regarding different underlayment options for your metal roofing, consult a professional to choose the most suitable one. Fort Bend Steel Supply has the best steel products. You can see for yourself when you visit us at 14038 S Gessner Rd, Missouri City, TX 77489. You can also contact us at (281) 499-5800.