When melting snow refreezes at a roof edge, the cause can involve the entire assembly. A careful winter discussion includes the building below the roof.
Begin with the assembly
Heat reaching the roof can contribute to uneven melting. Insulation, air sealing and appropriate ventilation may be part of the review, depending on the roof design.
Manufacturer and building-science guidance can explain these relationships, but the property needs its own assessment.
Plan a coordinated response
Record where the problem occurs and the conditions when it appears. Keep observations ground-based and discuss the issue with qualified providers.
Avoid assuming that a new gutter or roof covering alone will solve the problem. Use our winter guide to prepare questions about the roof, attic and drainage together.
Downloads and links
Use these resources.
DOE: Roof and attic ice-dam guidance
Building-science guidance on roof assemblies and ice dams.
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