[GFYS]

The ice is caused from poor insulation in the cielings and poor attic ventilation causing heat buildup in the attic and a "hot roof" which melts snow which runs down the roof to the eaves where it freezes and creates the ice dams. The remedy is to make the roof cold which means elimination of warm air in the attic spaces with better insulation and stopping any leaks of warm air into the space along with addiquate ventilation . A ratio of 1 sqft ventilation for every 150 sqft attic space is the common code requirement.

 

[GFYS]

The "rubber sheet" is usually a bitumin membrane like Grace Ice and Water Shield. While installation of water proof membrains or sealed felt products will eliminate leakage through the roof for at least awhile it will not eliminate the ice dams, ice cicles or the damage caused by ice buildup (be sure to guard electric meters, gas meters etc under these areas. ) The only other remedy would be installation of an electric grid to melt the ice dams along the eaves or an "ice melt sock". Basically both method work the same way by creating channels through the ice dam for water to run off of the roof. I have no experience with either.

 

[GFYS]

I dont see any ice damns on the garage. The porch is heated and the roof of the porch is melting. Dont argue with me.

 

[GFYS]

heated metal cable sold for exactly that purpose……..............done
done only if the goal is to melt ice and waste money.