Winter Roof Leaks and Ice Dams: Causes and Impact

Winter roof leaks and ice dams arise from weather conditions and inadequate roof maintenance. When snow accumulates on the roof and temperatures vary, freezing and thawing cycles can create prime conditions for leaks to develop. The resulting water damage can seriously affect the home’s interior, structural integrity, and energy efficiency.

What Causes Winter Roof Leaks?

When temperatures fluctuate around the freezing point, snow on the warmer parts of a roof can melt and trickle down to cooler edges where it refreezes. This process can cause water to creep under shingles or seep into tiny gaps and cracks, eventually reaching the attic space. Over time, repeated freeze-thaw cycles exacerbate these leaks, allowing more water infiltration.

Poor insulation and ventilation in the attic amplify the risk of a leaky roof by causing uneven roof surface temperatures. Rising heat from inside the home warms certain roof sections without proper insulation, leading to irregular melting. Effective ventilation and insulation work together to keep the roof uniformly cool, which is key in the prevention of ice dams while also reducing the likelihood of leaks caused by uneven melting and refreezing patterns.