Blistering on standing seam metal roofs is a problem where small bubbles or raised spots appear on the metal panels. This can happen due to moisture trapped under the finish coat, often caused by poor application or exposure to harsh weather conditions over time. The metal panels themselves are generally coated with a paint system designed to resist the elements, but if the paint or primer isn’t applied properly or is damaged, moisture can cause the layers to separate and form blisters. Sometimes, blistering also occurs because of incompatible coatings or when the metal wasn’t dried thoroughly before painting, leading to trapped moisture. To diagnose this yourself safely, start by visually inspecting your roof for raised spots or peeling paint. Check for any dents, scratches, or areas where the coating looks uneven. Be cautious climbing on the roof, using a sturdy ladder and non-slip shoes, or simply use binoculars to examine from the ground. Look for sections where the metal seems bubbled or where the paint is flaking, particularly after heavy rain or snow.
If you see clear signs of blistering, it’s a good idea to contact a professional roofer who specializes in metal roofing to prevent further damage. Ask them about their experience with standing seam metal and how they approach fixing blisters—whether that involves replacing panels, spot repairs, or refinishing the finish system. You might also want to ask about the paint system they use and whether it complies with your roof’s warranty requirements, as some manufacturers won’t honor warranties if improper coatings are applied. A good question to ask would be, “Can you confirm that any repair or repainting will preserve my roof’s warranty?” and “What steps do you take to ensure the roof won’t blister again after repair?” This way, you get a clear idea of their expertise and their commitment to lasting quality.