Icicles hanging off eaves is a very common sight in our neck of the woods.  Under insulated or under ventilated attic spaces, if not both, are mostly to blame.  Melting snow from the roof travels over the colder, unheated eve and freezes.  This process can create a backup of ice commonly known as an ice dam.  This protective barrier typically made with polymer-modified bitumen, helps protect this area because it sticks to the roof deck and to itself to seal the seams.  Code does not require this added protection on garages, but Economy Garages installs this protective layer on all buildings.