Ice dams form when warm air escaping from the living space heats the roof deck above the freezing point, melting snow that then refreezes at the cold eave overhang. The pooling water forces its way under shingles and causes interior leaks. The permanent fix addresses the root cause: improving attic insulation and ventilation to keep the roof deck uniformly cold. Temporary measures include installing extended ice-and-water shield membrane at eave edges and, in severe cases, self-regulating heated cable in gutters and valleys. Master Roofers offers all of these solutions.