Ankeny Gutter Replacement & Gutter Guard Installation

What actually causes an ice dam

Ice dams are widely blamed on gutters, and gutters are usually not the cause. A dam forms when the upper part of a roof is warmer than the edge. Snow on the warm section melts, the meltwater runs down, and when it reaches the cold overhang past the exterior wall it refreezes. That ridge of ice grows, and water backing up behind it finds its way under the shingles and into the wall or ceiling. The reason the upper roof is warm is almost always heat escaping from the living space below, which comes down to attic insulation and air sealing rather than anything to do with the gutter. What the gutter does control is what happens to the water once it gets to the edge. A gutter packed with ice gives meltwater nowhere to go and lets the dam build faster and thicker. A gutter that is correctly sized, correctly pitched, clear, and paired with heat cable keeps a channel open through the freeze. It is worth being clear about which problem you are solving: gutter work manages the symptom well, and insulation work addresses the cause.