Ice dam

Ice dams form when heat escaping from the attic warms the roof surface, melting snow on the upper roof. The meltwater flows down to the cooler eaves (overhangs, where heat doesn't reach) and refreezes — creating a ridge of ice that traps subsequent meltwater behind it. The trapped water can back up under shingles and into the attic, walls, and ceilings.

Ice dam damage is significant: ruined drywall, soaked insulation (which loses R-value when wet), damaged window and door framing, mold growth in concealed spaces, and deteriorated roof decking. Repair often runs into thousands or tens of thousands of dollars.

For gutter and roofing operators, ice dam-related work has two phases: emergency removal during winter (steam removal, channel cutting — never with hammers or salt, both of which damage shingles and gutters) and prevention work during off-season (improved attic insulation, attic ventilation, ice and water shield underlayment at eaves). The emergency removal is high-margin emergency dispatch work; the prevention is durable customer relationship work that often includes additional services beyond gutter repair.