The answer to 'ridge vent ice dams' is that ice dams forming at the ridge vent are a common problem that can lead to roof leaks and water damage. Ice dams occur when heat escapes the attic and melts snow on the roof, causing water to refreeze at the eaves and create a dam that traps additional meltwater.
The main causes are inadequate insulation and air sealing in the attic, which allows warm air to escape and melt the snow. Symptoms include icicles forming at the eaves and water backing up under the shingles. Solutions include improving attic insulation, sealing air leaks, and installing a heated cable system along the ridge vent to prevent ice dam formation.