When installing a standing seam metal roof, choosing the right underlayment is crucial for protecting your home from moisture and improving the longevity of the roof system. Underlayment is a layer installed between the metal panels and the roof deck, acting as a moisture barrier. For standing seam metal roofs, synthetic underlayments are generally the best choice because they offer excellent water resistance, durability, and tear strength. They are less prone to absorbing moisture compared to traditional felt options, which means they hold up better under metal roofing that can trap heat and condensation. Additionally, self-adhered membranes with rubberized asphalt layers provide an extra seal, especially recommended around valleys, penetrations, and eaves where leaks are more likely. Moisture can sometimes come from below the metal panels via condensation, so having a robust underlayment helps prevent water damage to the roof deck and interior ceilings.
To check if your underlayment is doing its job without removing the metal panels, you can look for signs like damp spots or mold in your attic, which might suggest moisture is getting through. During inspections, make sure the seams and edges of the underlayment are intact and that there’s no visible damage or buckling. It’s safe to look at the attic and roof surface for clues of water intrusion but avoid trying to remove metal panels yourself; this is best left to professionals because improper handling could void your roof warranty or damage the panels. When hiring a contractor, ask specific questions like, “What type and brand of underlayment do you recommend for standing seam metal roofing in this climate?” and “How do you ensure the underlayment is installed to prevent ice dams and condensation issues?” These questions show you’re informed and help ensure the best care for your roof’s long-term performance.