What Causes Ice Dams? Part I
By Jason Channell, The House Sleuth
(Diadem Property Inspections - Serving Southeast Michigan)
What Causes Ice Dams? Temperatures are dropping. On Friday, it started snowing as I drove off to pick up dinner. Granted, it didn't stick, but we all know winter is on its way. Every year I see Michigan homes damaged by ice dams. A lot of people have heard the term "ice dam," but don't really understand what it is, what it does, or how to prevent it. An ice dam is, essentially, a ridge of ice that forms at the edge of a roof. It prevents melting snow from draining off the roof, causing water to back up behind the dam, move back up the roof, and leak into the house. Here's the idea: We know snow melts when it is warmer than 32°F. And we understand from gravity that water will flow down the roof. But the roof isn't a uniform temperature. When it is warmer at the top, snow will melt. A...