The core idea
Uneven roof temperatures can melt snow that refreezes at colder eaves and backs water beneath roof coverings.
How the mechanism works
Heat loss warms upper roof areas while exposed eaves remain below freezing.
When it becomes relevant
Typical trigger: Snow cover, sun and subfreezing eaves.
Evidence that supports this interpretation
- Ice forms at eaves
- Leaks appear during thaw
- Attic heat-loss evidence is present
Evidence that weakens it
- Warm rain reproduces the same path
- No snow or freezing exists
- The leak is at a plumbing line
What this concept cannot prove alone
A single observation, image or meter reading cannot confirm the complete failure pathway. Use this concept to form better questions, compare alternatives and decide which safe observation would be most informative next.
Safety and professional boundary
Do not climb icy roofs or chip ice with tools that can damage roofing.
Primary references for this topic family
These references ground the general building-science or safety context. They do not diagnose a specific house, replace local requirements or certify a repair.
US Department of Energy · government retrofit guidanceAttic Air Sealing GuideAttic bypasses, air leakage and retrofit sequencing.Verified 2026-07-20 · review due 2027-01-20Open source ↗US Department of Energy · government homeowner guidanceConsumer Guide to Durable AtticsAttic moisture control, ventilation, air sealing and durable retrofit sequencing.Verified 2026-07-20 · review due 2027-01-20Open source ↗US Environmental Protection Agency · government guidanceMoisture Control Guidance for Building Design, Construction and MaintenanceMoisture sources, transport, design, construction and maintenance controls.Verified 2026-07-20 · review due 2027-01-20Open source ↗US Department of Energy · government research libraryBuilding America Publications and Solution CenterBuilding enclosure, HVAC, windows, indoor air and high-performance housing research.Verified 2026-07-20 · review due 2027-01-20Open source ↗
Observe→Compare triggers→Repair source→Verify outcome
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