The answer to 'why is my metal roof ice dams' is that ice dams can form on metal roofs when snow and ice melt and then refreeze at the roof's edge. This creates a barrier that prevents proper drainage, leading to further ice buildup. Common causes include poor insulation, inadequate ventilation, and excessive snow accumulation.
Ice dams on a metal roof can cause significant damage, including leaks, water intrusion, and even the collapse of the roof structure. It's important to address the issue promptly to prevent further problems.