What causes ice buildup on the edges of my roof?

Typically, snow is melted by heat escaping through the roof. The water refreezes at the overhang at the bottom of the roof because it is colder than the rest of the roof.
What weather conditions create ice buildup?
First of all, there must be snow on the roof. Secondly, the outside temperature must be below freezing. The longer snow is on the roof and the longer the temperature remains below freezing, the more likely it is that ice buildup and leakage will occur.

Posted on by opadmin.