An ice dam forms when heat escaping from the living space warms the roof deck, melts the snow lying on it, and that meltwater runs down to the cold eave — which is beyond the heated envelope — and refreezes there. The ridge of ice that builds up holds the next round of meltwater behind it, and that standing water works back up under the shingles, which are designed to shed water running downhill, not to sit in it. The fix is not to chip at the ice. It is to stop the heat escaping: attic insulation depth and air sealing first, then balanced intake and exhaust ventilation so the deck stays at outside temperature. Self-adhering ice-and-water membrane at the eaves and in the valleys is the belt-and-braces defence, and we install it as standard rather than as an upgrade.
This answer is written from what we actually do. If you want it applied to your roof specifically, an inspection and written estimate are free — call (856) 292-7046 or reach your nearest of our 15 offices.
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Roof Installation · Roof Repair · Roof Replacement · Gutter Installation & Guards · Roof Inspection · Storm Damage Roof Repair
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