10 Best Underlayment For Metal Roof 2025 in the United States

The FT Synthetics Platinum HT Butyl Self Adhering Underlayment stands out as a solid choice for those looking to install or upgrade a metal roof. One of its key strengths is the 100% butyl composition, which ensures a strong bond to plywood or OSB roof decks. This self-adhering feature makes installation easier, especially for DIY enthusiasts or contractors. With a thickness of 41 mils, it provides robust protection and durability. Additionally, it is compatible with low slope roofing materials such as EPDM and TPO, which is a plus for varied projects.

Water resistance is another highlight; the underlayment offers watertight laps, effectively preventing leaks and ensuring longevity in various weather conditions. Its temperature tolerance and UV resistance make it suitable for diverse climates, enhancing its utility across regions.

While it performs well, there are some factors to consider. The coverage per roll is 200 square feet, which may require purchasing multiple rolls for larger roofs, potentially increasing costs. Its weight at 40 lbs per roll can also be cumbersome and may require additional handling considerations during installation. This product is ideal for homeowners or professionals seeking reliable underlayment for metal roofs, particularly where low slope options are involved. However, those with larger projects should plan for extra rolls and consider the installation weight.

The SIPA 100 GSM Synthetic Waterproof Roof Underlayment is designed for both residential and commercial roofs, including metal roofing applications. It uses a non-woven polypropylene material laminated with polyethylene, which makes it waterproof and durable. Its 100 GSM thickness provides a solid barrier without being too bulky, balancing protection and ease of handling. One of its strong points is its excellent water resistance, ensuring your roof stays dry under harsh weather conditions. It also offers UV resistance for up to 60 days, which is helpful during installation before the final roofing goes on.

The material is stable and won’t buckle, warp, or crack, which means it maintains a smooth surface beneath shingles or metal sheets. Installation should be straightforward for most users since it comes in a large 48-inch wide roll that covers 1,000 square feet, minimizing the number of seams and overlaps. The product meets key industry standards (ASTM D4869, ASTM D226) and has relevant approvals, reflecting its reliability.

Weighing 80 pounds per 10-roll package, it might be somewhat heavy to handle alone, which could make installation more challenging for some. For those seeking a dependable, waterproof underlayment with good UV protection and sturdy material suitable for metal or asphalt roofs, this product is a strong choice. It is advisable to plan ahead for its weight and size during installation.

The Tyvek Protec 120 Roof Underlayment is a well-regarded option for those looking to install or repair metal roofs, as well as other roofing types like asphalt and cedar shingles. One of its standout features is its trusted quality from DuPont Tyvek, which brings durability and reliability to your roofing project. With a decent thickness of 6.3 inches, it provides a solid barrier against moisture, which is crucial for preventing leaks and damage over time. Additionally, the underlayment boasts excellent water resistance and UV protection, vital for roofs exposed to harsh weather conditions and sunlight.

Another strength is its unique embossed pattern designed to improve traction and grip, making installation safer and easier for users working on roofs. This feature can be particularly beneficial for DIY enthusiasts who may not have professional experience with roofing.

This product has a lot going for it, though there are some considerations to keep in mind. Its weight at 24.6 pounds might make it somewhat cumbersome for single-person handling, particularly during installation. The Tyvek Protec 120 serves as a solid choice for underlayment in metal roofing projects, particularly for those valuing durability and ease of installation. Just be mindful of its weight during handling.