Ice dams are thick ridges of solid ice that build along the eaves (bottom edges) of your roof. These dams can tear down gutters, loosen shingles, and cause water to back up and pour into your home. When this occurs, paint begins to peel, floors become warped and ceilings stain or even begin to sag. Moreover, ice dams create soggy insulation in the attic, which eats into resale value and becomes a breeding ground for mildew and mold.
View the short presentation below, courtesy of Mike Otto owner and CEO of Fair & Square Remodeling, to learn more about how ice dams form, how you can prevent them from forming and how to quickly fix them if they’ve already formed. Source