Standing seam metal roofs require an underlayment primarily to provide extra protection against water infiltration, especially from wind-driven rain and ice dams. The underlayment acts as a secondary barrier beneath the metal panels, helping prevent leaks if the outer metal surface is compromised or during heavy storms. Typically, synthetic felt or a peel-and-stick membrane is recommended because these materials resist moisture better than traditional asphalt felt. Underlayment also protects the roof deck during installation before the metal panels are fully secured. Keep in mind that building codes and manufacturer warranties often specify minimum underlayment standards, so using approved materials is essential to maintain roofing performance and warranty coverage.
To check your underlayment safely, you can inspect the roof’s edges or attic penetrations without stepping onto the roof. Look for signs of moisture, staining, or visible damage that might indicate underlayment problems. If your standing seam roof is leaking or you suspect improper installation, call a professional roofer experienced with metal roofs to diagnose the issue thoroughly. When speaking with a contractor, ask: “What type of underlayment do you recommend for this climate and why?” and “How will you ensure the underlayment installation complies with the metal panel manufacturer’s warranty requirements?” These questions help ensure you get a durable, code-compliant roof that protects your home for years to come.